STOCKHOLDERS' EQUITY - Schedule of Changes in the Balance of AOCL, Net of Tax (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning Balance	$ 2,896	$ 479	$ 1,449	$ (776)
Other comprehensive income before reclassifications			(30)	(53)
Total reclassified from AOCL			698	923
Other comprehensive income, net of tax	186	318	668	870
Ending Balance	3,937	1,002	3,937	1,002
Recognition of previously deferred postretirement benefit plan amounts	227	300	681	900
Postretirement Benefit Plans
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning Balance			(14,254)	(12,559)
Other comprehensive income before reclassifications			0	0
Total reclassified from AOCL			681	900
Other comprehensive income, net of tax			681	900
Reclassification of income tax effects from tax reform				(2,396)
Ending Balance	(13,573)	(14,055)	(13,573)	(14,055)
Other, net
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning Balance			(67)	20
Other comprehensive income before reclassifications			(30)	(53)
Total reclassified from AOCL			17	23
Other comprehensive income, net of tax			(13)	(30)
Reclassification of income tax effects from tax reform				(12)
Ending Balance	(80)	(22)	(80)	(22)
AOCL
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning Balance	(13,839)	(14,395)	(14,321)	(12,539)
Other comprehensive income, net of tax	186	318	668	870
Reclassification of income tax effects from tax reform				(2,408)
Ending Balance	(13,653)	(14,077)	(13,653)	(14,077)
Recognition of net actuarial losses
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Total reclassified from AOCL			861	1,092
Recognition of previously deferred postretirement benefit plan amounts	287	364
Amortization of net prior service credits
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Total reclassified from AOCL			(180)	(192)
Recognition of previously deferred postretirement benefit plan amounts	$ (60)	$ (64)
Other
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Total reclassified from AOCL			$ 17	$ 23

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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