CORNELIA G. KENNEDY, Circuit Judge.
Yard-Man appeals the District Court’s grant of summary judgment that it breached its collective bargaining agreement with appellees, United Automobile, Aerospace and Agricultural Implement Workers of America (UAW or Union) and its Local 134, UAW, by terminating the life and health insurance benefits of Yard-Man’s retired employees at the expiration of the collective bargaining agreement and in substituting the payment of present cash value for its bargained obligation to purchase annuities to fund supplemental pensions. We affirm the District Court’s holding that the retirees are entitled to continued insurance benefits but reverse its holding that YardMan could not, even with the consent of its pensioners, substitute cash value for annuities.
In August 1974, Yard-Man and the UAW entered into a collective bargaining agreement covering employees at Yard-Man’s Jackson, Michigan, plant. The contract bore a stated expiration date of June 1, 1977. Less than a year after the signing of the contract the plant closed.
In April 1977, Yard-Man notified its Jackson retirees that existing health and life insurance benefits would terminate upon the collective bargaining agreement’s expiration. Soon thereafter, the UAW filed grievances claiming that Yard-Man’s unilateral action in terminating the retirees’ life and health insurance violated that agreement. When Yard-Man refused to arbitrate, the UAW filed this action under § 301(a) of the National Labor Management Relations Act of 1947, 29 U.S.C. § 185 (1976), seeking to compel arbitration. Alternatively, it sought on behalf of the retirees specific performance of Yard-Man’s obligation to provide health and life insurance benefits beyond the term of the collective bargaining agreement. It also sought damages to compensate retirees who had paid insurance premiums or medical expenses since the expiration of the collective bargaining agreement.
In a second count, the UAW requested specific performance of Yard-Man’s acknowledged obligation under the collective bargaining agreement to purchase annuities to fund its supplemental pension plan. After this suit was filed, and without notice or consultation with the UAW, Yard-Man distributed lump sum payments of the present value of the supplemental pension rights directly to each retiree.
The UAW waived its demand for arbitration and the parties filed cross-motions for summary judgment. Relying solely upon the language of the collective bargaining agreement, the District Court found that Yard-Man breached its contractual obligations when it cancelled the retirees’ insurance upon expiration of that agreement. Yard-Man was ordered to provide health and life insurance for its retirees and their dependents, and to reimburse employers for losses due to termination of this insurance. The District Court also found that YardMan had failed to purchase annuities to fund the supplemental pension plan. It rejected Yard-Man’s claim that it had performed this obligation by paying the cash value of the annuities to individual employees. The court ordered Yard-Man to purchase the collectively bargained annuities upon repayment by retirees of the lump sum distributions theretofore made. Damage questions were reserved.
The District Court certified its judgment under 28 U.S.C. § 1292(b) as a decision involving a controlling question of law as to which there is substantial ground for difference of opinion. This court permitted [1479]*1479Yard-Man’s appeal from the summary judgment, granting specific performance on both counts, and the UAW’s cross-appeal from that portion of the District Court’s judgment requiring repayment of the cash distribution made in lieu of supplemental pension annuities, as a condition of receiving such an annuity.
Resolution of the UAW’s claim of lifelong insurance benefits for retirees requires interpretation of key contractual language in the collective bargaining agreement. The Union’s second claim, the undisputed failure by Yard-Man to purchase the annuities called for in the collective bargaining agreement, requires evaluation of Yard-Man’s affirmative defense of substituted performance and the legitimacy of offering such performance directly to the retirees after suit had been filed and without notice to the union.
I. The Parties Intended to Create Lifelong Vested Insurance Benefits for the YardMan Retirees
The District Court properly recognized that whether retiree insurance benefits continue beyond the expiration of the collective bargaining agreement depends upon the intent of the parties. Clearly the parties to a collective bargaining agreement may provide for rights which will survive termination of their collective bargaining relationship. John Wiley & Sons v. Livingston, 376 U.S. 543, 555, 84 S.Ct. 909, 917, 11 L.Ed.2d 898 (1964). The parties may, for example, provide retiree insurance benefits which survive the expiration of the collective bargaining agreement. Upholsterer’s International Union v. American Pad & Textile Co., 372 F.2d 427, 428 (6th Cir.1967); International Union, UAW, Local 784 v. Cadillac Malleable Iron Co., Inc., No. G82-75-CA1 (W.D.Mich. April 20,1982); American Standard, Inc., 57 Lab.Arb. (BNA) 698 (1971) (Warns, Arb.); Roxbury Carpet Co. and Textile Workers of America, AFL-CIO, 73-2 Lab.Arb. Awards (CCH) 18521 (1973) (Summers, Arb.). Any such surviving benefit must necessarily find its genesis in the collective bargaining agreement. See John Wiley & Sons, supra, 376 U.S. at 550, 555, 84 S.Ct. at 914, 917; Allied Chemical & Alkali Workers v. Pittsburgh Plate Glass, 404 U.S. 157, 181 n. 20, 92 S.Ct. 383, 398 n. 20, 30 L.Ed.2d 341 (1971); Local 1251, International Union, UAW v. Robertshaw Controls Co., 405 F.2d 29, 33 (2d Cir.1968); American Pad, supra, 372 F.2d at 427-28.
The enforcement and interpretation of collective bargaining agreements under § 301 is governed by substantive federal law. Textile Workers Union v. Lincoln Mills, 353 U.S. 448, 456, 77 S.Ct. 912, 917, 1 L.Ed.2d 972 (1957). However, traditional rules for contractual interpretation are applied as long as their application is consistent with federal labor policies. Id. at 457, 77 S.Ct. at 918. See John Wiley, supra, 376 U.S. at 548, 84 S.Ct. at 913; Transportation-Communication Employees Union v. Union Pacific R.R., 385 U.S. 157, 160-61, 87 S.Ct. 369, 371-72, 17 L.Ed.2d 264 (1966); Kellogg Company v. NLRB, 457 F.2d 519, 524 (6th Cir.1972).
Many of the basic principles of contractual interpretation are fully appropriate for discerning the parties’ intent in collective bargaining agreements. For example, the court should first look to the explicit language of the collective bargaining agreement for'clear manifestations of intent. Kellogg Co., supra, 457 F.2d at 524. The intended meaning of even the most explicit language can, of course, only be understood in light of the context which gave rise to its inclusion. See Randall v. Lodge No. 1076, International Ass’n of Machinists and Aerospace Workers, AFL-CIO, 648 F.2d 462 (7th Cir.1981); Forrest Industries, Inc. v. Local Union No. 3-436, International Woodworkers of America, AFL-CIO, 381 F.2d 144,146 (9th Cir.1967); United Steelworkers of America v. American Manufacturing Co., 363 U.S. 564, 570, 80 S.Ct. 1343, 1364, 4 L.Ed.2d 1403 (1960) (Brennan, J., concurring). The court should also interpret each provision in question as part of the integrated whole. If possible, each provision should be construed consistently with the entire document and the relative positions and purposes of the par[1480]*1480ties. Kellogg Co., supra, 457 F.2d at 524. See Randall, supra, 648 F.2d at 466; Florida Canada Corp. v. Union Carbide & Carbon Corp., 280 F.2d 193 (6th Cir.1960). As in all contracts, the collective bargaining agreement’s terms must be construed so as to render none nugatory and avoid illusory promises. See Cordovan Associates, Inc. v. Dayton Rubber Company, 290 F.2d 858, 861 (6th Cir.1961). Where ambiguities exist, the court may look to other words and phrases in the collective bargaining agreement for guidance. Variations in language used in other durational provisions of the agreement may, for example, provide inferences of intent useful in clarifying a provision whose intended duration is ambiguous. See American Pad, supra, 372 F.2d at 427-28; Kellogg Co., supra, 457 F.2d at 524. Finally, the court should review the interpretation ultimately derived from its examination of the language, context and other indicia of intent for consistency with federal labor policy. This is not to say that the collective bargaining agreement should be construed to affirmatively promote any particular policy but rather that the interpretation rendered not denigrate or contradict basic principles of federal labor law.
Application of these basic rules of construction to the present case demonstrates the correctness of the District Court’s conclusion that the parties intended to create nonterminating lifelong insurance benefits for the Yard-Man retirees.1
The key provision of the collective bargaining agreement, Article XVII, Section 4, states:
When the former employee has attained the age of 65 years then:
(1) The Company will provide insurance benefits equal to the active group benefits ... for the former employee and his spouse.
(Emphasis added.)
Appellant Yard-Man asserts that this provision is plain and unambiguous on its face. Under Article XVII, Section 1 of the agreement, active employee benefits expressly terminate one month after an employee’s “layoff.” The benefits of all active employees thus terminated upon plant closure. Yard-Man argues that since the insurance benefits of former employees are defined as “equal” to active employee benefits, those benefits must be equivalent in all respects including duration. Retiree benefits could then also be terminated at plant closure or, as actually occurred, with the expiration of the collective bargaining agreement.
We agree with the District Court that the key provision of the collective bargaining agreement is ambiguous. The language “will provide insurance benefits equal to the active group” could reasonably be construed, if read in isolation, as either solely a reference to the nature of retiree benefits or as an incorporation of some durational limitation as well. This phrase is no less ambiguous as to intended duration than language construed as creating continuing benefits in the various eases and arbitration decisions cited by the parties. See, e.g., American Pad, supra, 372 F.2d at 427 (“will continue to provide”); Cadillac Malleable Iron Co., supra, slip op. at 8 (“will pay the cost ... for retired employees”); Roxbury Carpet, supra, 73-2 Lab.Arb. Awards ¶ 8521 (“shall continue to receive”); Wellman Dynamics and UAW, Loc. No. 804., Amer.Arb. Assoc. Case No. 54-30-0505-72 (1973) (Herman, Arb.) (“shall provide”).
This ambiguity requires that we look to other provisions of the collective bargaining agreement for evidence of intent and an interpretation which is harmonious with the entire document. This examination per[1481]*1481suades us that Yard-Man and the Union intended to create vesting insurance benefits in the Yard-Man retirees which continue beyond the life of the collective bargaining agreement.2
First, termination of insurance benefits for active employees was explicitly and clearly set out and yet under conditions— the layoff of seniority employees — typically inapplicable to retirees.3 Moreover, there are variations in the duration of insurance benefits available to active employees dependent upon their seniority.4 These variations and the impracticality of hinging retiree benefits to events as unpredictable and unstable as active worker layoffs make it improbable that retiree benefits were intended to depend in duration upon the fortunes of the active employees. Yard-Man’s own course of conduct in continuing retiree insurance benefits after plant closure beyond the point as which insurance benefits could have been terminated for active employees indicates that it did not consider retiree benefits to be tied to the durational, limitations of that active group.5
Second, the insurance provisions limit health insurance coverage for a retiree’s spouse and dependent children in case of the retiree’s death to expiration of the collective bargaining agreement.6 While this limitation does not preclude an intent to also terminate the retiree’s benefits with the expiration of the collective bargaining agreement in any event, it is more reasonable to infer that the spouse-dependent child provision was meant as an exception to the anticipated continuation of benefits beyond the life of the collective bargaining agreement.
Third, the retiree insurance provisions, Article XVII, Section 1, contain a promise that the company will pay an early retiree’s insurance upon such retiree reaching age 65 but that the retiree must bear the cost of company insurance until that time. Since an employee is entitled under the collective bargaining agreement to retire at 55, the company’s promise could remain outstanding for a ten-year period. If retiree insurance benefits were terminated at the end of the collective bargaining agreement’s three-year term, this promise is completely illusory for many early retirees under age 62.
Fourth, the inclusion of specific durational limitations in other provisions of the current collective bargaining agreement suggests that retiree benefits, not so specifical[1482]*1482ly limited, were intended to survive the expiration of successive agreements in the parties’ contemplated long term relationship. Article XIX, for example, provides that “savings and pension plan programs” continue only for the duration of the collective bargaining agreement. No such specific limitation was provided to similarly restrict payment of retiree insurance benefits to the life of the collective bargaining agreement.7
Finally, examination of the context in which these benefits arose demonstrates the likelihood that continuing insurance benefits for retirees were intended. Benefits for retirees are only permissive not mandatory subjects of collective bargaining. Pittsburgh Plate Glass Co., supra, 404 U.S. at 181-82, 92 S.Ct. at 398-99. As such, it is unlikely that such benefits, which are typically understood as a form of delayed compensation or reward for past services, would be left to the contingencies of future negotiations. See, e.g., Cadillac Malleable Iron, supra, slip op. at 12-13; Cantor v. Berkshire Life Ins. Co., 171 Ohio 405, 171 N.E.2d 518 (1960); Roxbury Carpet, supra, 73-2 Lab.Arb. Awards It 8521, p. 4940. The employees are presumably aware that the union owes no obligation to bargain for continued benefits for retirees. If they forego wages now in expectation of retiree benefits, they would want assurance that once they retire they will continue to receive such benefits regardless of the bargain reached in subsequent agreements. Contrary to Yard-Man’s assertions, the finding of an intent to create interminable rights to retiree insurance benefits in the absence of explicit language, is not, in any discernible way, inconsistent with federal labor law.8
Further, retiree benefits are in a sense “status” benefits which, as such, carry with them an inference that they continue so long as the prerequisite status is maintained. Thus, when the parties contract for benefits which accrue upon achievement of retiree status, there is an inference that the parties likely intended those benefits to continue as long as the beneficiary remains a retiree. This is not to say that retiree insurance benefits are necessarily interminable by their nature. Nor does any federal labor policy identified to this Court presumptively favor the finding of interminable rights to retiree insurance benefits when the collective bargaining agreement is silent. Rather, as part of the context from which the collective bargaining agreement arose, the nature of such benefits simply provides another inference of intent. Standing alone, this factor would be insufficient to find an intent to create interminable benefits. In the present case, however, this contextual factor buttresses the already sufficient evidence of such intent in the language of this agreement itself.
Yard-Man urges that a general durational clause which provided that the collective bargaining agreement should remain in force until June 1, 1977 demonstrates an intent that all benefits described in the agreement also terminate at that date. We do not agree. The clause does not specifically refer to the duration of benefits. The persuasive considerations we have discussed demonstrate that retiree benefits were in[1483]*1483tended to outlive the collective bargaining agreement’s life and outweigh any contrary implications derived from a routine duration clause terminating the agreement generally. Such an intent takes precedence over a non-specific, general clause.
II. The Purchase of Annuities
Yard-Man agreed in the collective bargaining agreement to purchase annuities to fund its supplemental pension plan in the event of business failure. It is undisputed that Yard-Man has failed to do so. Instead, after the commencement of this suit, YardMan distributed directly to the individual retirees lump sum payments of the present value of these pension benefits.9 The UAW was neither consulted or notified prior to this distribution. Noting that the required annuities were available but not purchased because they would be uneconomical for Yard-Man, the District Court found YardMan in breach of its contractual obligations and ordered specific performance.10
Yard-Man asserts two defenses to liability which were rejected without discussion by the District Court: accord and satisfaction (substituted performance) and estoppel. Yard-Man argues that its offer of substituted performance in the form of lump sum distribution checks was accepted and the distribution retained by the retirees, thereby discharging its original obligation. Moreover, Yard-Man contends that since it could not invest or utilize those funds after the retirees accepted them, the retirees and the union which is suing on their behalf are estopped from seeking specific performance by virtue of Yard-Man’s detrimental reliance.11 The UAW in response asserts that [1484]*1484neither defense can be effective in the present case because Yard-Man failed to notify the retirees’ legal representative, the UAW, of the proposed substituted performance.
The contentions of the parties raise two related legal issues. First, whether retirees may, consistent with federal labor law, settle their contractual disputes over benefits directly with their former employer by means of accord and satisfaction without notice to or the consent of their union? Second, even if they may, are such direct settlements between retirees and the former employer, entered into without notice to or consent of the union, precluded once the union undertakes the legal representation of the retirees in a § 301(a) litigation?
The prime consideration in resolving the initial question must be whether direct settlement between retirees and their former employer without notice to or the consent of the union is in any fashion inconsistent with the national labor statutes and their primary purpose of promoting industrial peace. Lincoln Mills, 353 U.S. at 457, 77 S.Ct. at 918. See United Ass’n of Journeymen, Plumbers & Pipefitters v. Local 334, United Ass’n of Journeymen, Plumbers & Pipefitters, 452 U.S. 615, 636-37, 101 S.Ct. 2546, 2557-58, 69 L.Ed.2d 280 (1981) (Stevens, J., dissenting). See generally 29 U.S.C. § 151 (1976).
Initially, a distinction must be recognized between retiree contractual benefits under a collective bargaining agreement and the terms and conditions of employment created by that agreement for active employees. In the case of active employees, Congress has spoken directly on the issue of settlements between employer and employee. Title 29 U.S.C. § 159(a) specifically permits “adjustments” between employer and employee without intervention of the union so long as the agreement is not inconsistent with the terms of the bargaining agreement and the union has been given an opportunity to be present.
In Pittsburgh Plate Glass Co., 404 U.S. at 176-82, 92 S.Ct. at 396-99, the United States Supreme Court held that employers are under no obligation to bargain with unions over benefits for already retired workers. The Court reasoned that retired workers were neither “employees” under federal labor law nor properly members of the appropriate bargaining unit. As such, benefits for retired workers are not a mandatory but rather only a permissive subject of collective bargaining. Id. at 170, 180-82, 92 S.Ct. at 393, 398-99. Similarly, the union has no duty to represent retirees with the employer, although it may choose to do so. Id. at 181 n. 20, 92 S.Ct. at 398 n. 20. Thus, since retirees are not employees under the Act, § 159(a) itself clearly does not apply.
There is no provision parallel to § 159(a) relating to settlements between retirees and former employers. Nor would creation of a § 159(a) type notice by analogy be appropriate. Section 159(a) represents a policy favoring settlements while protecting the union’s interest in the integrity of the collective bargaining agreement and the terms and conditions of employment of the active employees. The statute requires notification to the union prior to employer settlements with active employees out of recognition of the union’s status as the active employee’s sole bargaining representative. In the case of retirees, who are not employees or members of the bargaining unit and whose relationship to the employer and union is not directly controlled by the labor statutes, this primary rationale for notification no longer exists. While the union may have bargained for and received benefits for retirees, it does not have the same interest in the enforcement of those contractual rights on the behalf of individual retirees that it has in the terms and conditions of employment of active employees. Unlike the active employees, retirees [1485]*1485face no restrictions whatever in seeking fulfillment of contractual benefits directly from their former employer. See Rehmar v. Smith, 555 F.2d 1362, 1370 n. 6 (9th Cir.1976); 404 U.S. at 181 n. 20, 92 S.Ct. at 398 n. 20. See also Smith v. Evening News Ass’n, 371 U.S. 195, 200-201, 83 S.Ct. 267, 270-271, 9 L.Ed.2d 246 (1962). Similarly, the union is under no obligation to seek enforcement of such rights. See, e.g, Nedd v. United Mine Workers of America, 556 F.2d 190, 200 (3d Cir.1977).
While a collective bargaining agreement is not simply an ordinary contract, see, e.g., Hendricks v. Airline Pilots Association, International, 696 F.2d 673, 676 (9th Cir.1983), the vested rights of a retiree are essentially contractual in nature. Cf. 404 U.S. at 181 n. 20, 188, 92 S.Ct. at 398 n. 20, 402. Thus, the relationship of retiree and employer is unadorned with those special considerations peculiar to the relationship between an active employee, his union and the employer which justified creation of those minimal notice requirements that do exist for active employees under the national labor laws.12 In settling a claim for vested benefits, the retiree does not modify the collective bargaining agreement. Nor can the retiree affect the terms and conditions of employment by doing so, as an active employee might upon direct settlement of a grievance with the employer. A direct settlement between an active employee and the employer which is inconsistent with the terms of the collective bargaining agreement might, for example, result in an unfair labor practice. This is not the case for retirees who are free to settle their differences with the former employer on whatever terms desired, including a compromise over disputed contractual benefits.
Active union members need their joint common strength to bargain most effectively for improvements in wages, hours and working conditions. That need is explicitly recognized in the federal labor statutes. 29 U.S.C. §§ 151, 157, 159. See also Pittsburgh Plate Glass, 404 U.S. at 174-75, 175 n. 15, 92 S.Ct. at 395-96 n. 15. As retirees, however, former employees do not need that joint common strength to enforce their vested contractual rights against their former employer. See 404 U.S. at 181 n. 20, 92 S.Ct. at 398 n. 20. See also id. at 172-73, 92 S.Ct. at 393-95; Pittsburgh Plate Glass Co., Chemical Div. v. NLRB, 427 F.2d 936, 942 n. 9, 946 (6th Cir.1970), aff’d 404 U.S. 157, 92 S.Ct. 383, 30 L.Ed.2d 341 (1971). Each retiree has an undisputable and effective remedy against the employer for a breach of contract under § 301(a).13 See 404 U.S. at 176, 188, 92 S.Ct. at 396, 402. The retiree, no longer a member of the union, may not want the union to be notified of what the retiree wishes or intends to do. This Court is unable to discern any policy basis in federal labor law which would be served by rejecting application of the well-established principle of accord and satisfaction to disputes over retiree benefits merely because they were created in collective bargaining agreements. Such a rejection would not in any fashion promote labor peace or the interests of the individual retirees.
The case for creating such a notice rule in the narrow circumstances in which a union has actually undertaken representation of the retirees in a § 301(a) litigation is somewhat more compelling. Under these circumstances the union has clearly manifested its interest in the preservation of the disputed benefits and presumably believes [1486]*1486collective legal representation to be in the best interests of its former members. Yet, all of the reasons for not creating such a notice requirement in the absence of a union instituted § 301 suit apply with equal force when the union has undertaken such representation. Nor is there any new discernible inconsistency between direct retiree-employer settlements and national labor policies brought about by the union’s active role in initiating a § 301(a) litigation.14 Most importantly, we do not believe that the union’s interest in the retirees’ contractual claims is sufficient to either demand judicial creation of a procedural notice requirement or override the right of individual retirees to settle their contractual disputes directly with their former employer.
The UAW contends that there can be no meeting of the minds on a substituted performance when the legal representative of the suing party has not been contacted. Since this is not true in normal civil litigation, see, e.g., Lewis v. S.S. Baune, 534 F.2d 1115, 1122 (5th Cir.1976); Cook v. Moran Atlantic Towing Corp., 76 F.R.D. 481 (S.D. N.Y.1977); Krause v. Hartford A. & I. Co., 331 Mich. 19, 26-27, 49 N.W.2d 41 (1951), the validity of this assertion depends upon the existence of special considerations particular to federal labor law. As discussed above no such special considerations exist.
We do not suggest that the union has no standing to bring a suit on behalf of retirees. United Steelworkers of America, AFL-CIO v. Canron, Inc., 580 F.2d 77, 80 (3d Cir.1978). As a signatory to the contract it could bring an action for the third party beneficiary retirees. Nor do we suggest that the union is without interest in the outcome of potential settlements between the employer and the retirees. See, e.g., 404 U.S. at 176 n. 17, 92 S.Ct. at 396 n. 17. See also Toensing v. Brown, 528 F.2d 69, 72 (9th Cir.1975); Rosen v. Public Service Electric and Gas Company, 477 F.2d 90, 94 n. 8 (3d Cir.1973); UAW v. Acme Precision Products, 515 F.Supp. 537, 539-40 (E.D. Mich.1981). Clearly the union’s efforts in ensuring employer compliance with all of the terms of a collective bargaining agreement are a significant consideration for the active employees when choosing to retain the union as their exclusive bargaining representative. In this sense the union has a direct interest in maintaining the integrity of the retiree benefits created by the collective bargaining agreement.15 See 404 U.S. at 176 n. 17, 92 S.Ct. at 396 n. 17. Yet, the issue here is not whether or not the union has some residual representation interest in the fate of former members of the bargaining unit.16 Rather, the issue essentially concerns the right of individual retirees to resolve disputes over contractual benefits directly with the former employer without the union’s involvement. There are simply no discernible federal labor law policies which restrict the right of individual retirees to settle their contractual disputes [1487]*1487directly with their former employer without notice to the union.
Even accepting that some minimal form of notice to the union may be desirable once the union has undertaken legal representation on the retirees’ benefits, there are compelling reasons why we should not adopt a judicially mandated procedural requirement. First, it is important that in requiring notice we would be creating a procedural rule, something courts are reluctant to do, unless required by due process. There would be the problem, of defining when notice must be given. Should it be required for every settlement with every retiree? Clearly this would be inappropriate. Yet which rights or benefits are so significant that notice would be required? And by what measure do the district courts determine that question? This procedural rule would presumably be applied not only in this litigation, but in a myriad of unknown pending controversies. We cannot know its effect in those unknown cases. Without clear justification of significance beyond the special circumstances presented in the case at bar this uncertainty strongly cautions against judicial adoption of any rule.
This is particularly true where, as in this case, the law already provides protection against the harm perceived. If, on remand, the District Court determines that the retirees had been victims of overreaching, the present settlements could be set aside. See, e.g., S.S. Brame, 534 F.2d at 1122. Collectively bargained benefits for retirees have existed for scores of years now and so far as can be determined there has been no need for such notice. This is another pragmatic reason for not creating such a duty now in the absence of some clear policy reason to do so.
In the present case the District Court held that, as a matter of law, YardMan could not provide a substituted performance in accord and satisfaction17 of contractual obligations to the retirees. Since we have found this to be in error, it is necessary to determine what principles of accord and satisfaction should be applied. Even though essentially contractual in nature, the disputed retiree benefits in this case nevertheless arise under a collective bargaining agreement and may be, as here, the subject of a federal suit under § 301 of the National Labor Relations Act. Under these circumstances, it is clear that it is federal substantive law which controls resolution of the contractual dispute. Lincoln-Mills, 353 U.S. at 456-57, 77 S.Ct. at 917-18. In the absence of controlling federal law principles, however, we may look for guidance to general common law principles, including the substantive law of the state in which the contract arose. These borrowed principles in this context, of course, are “absorbed as federal law” and become the federal common law of labor disputes. See id. at 457, 77 S.Ct. at 918. The principles of accord and satisfaction are well established in both the general common law and the law of Michigan where the present contract originates. The basic elements of this affirmative defense align themselves with normal contract principles of offer and acceptance. There must be a disputed claim,18 a substituted performance agreed [1488]*1488upon and accomplished, and valuable consideration. E.g., Risk v. Wells, 362 Mich. 414, 420,107 N.W.2d 776 (1961); 262 (1933). See also Keppard v. International Harvester Co., 581 F.2d 764 (9th Cir.1978) (applying California law); Brock & Blevins Company v. United States, 343 F.2d 951, 955 (Ct.Cl. 1965). See generally 6 Corbin on Contracts § 1276 (1962 & Kaufman, Supp.1982); 5 Williston on Contracts § 680 at 259-61 (3d Ed.1961). For the reasons already discussed we see no discernible inconsistency between these general principles and federal labor law.
The factual predicates for YardMan’s defense remain unresolved and summary judgment, therefore, is inappropriate. On remand the District Court must apply the basic elements of the affirmative defense of accord and satisfaction to determine whether such defense is viable. The court should also consider any contention that the actions of Yard-Man constituted overreaching. We affirm in part and reverse in part and remand this issue to the District Court for further proceedings consistent with this opinion.