STOCKHOLDERS' EQUITY - Schedule of Changes in the Balance of AOCL, Net of Tax (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 24, 2018	Jun. 30, 2019	Jun. 24, 2018
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning Balance	$ 2,522	$ (111)	$ 1,449	$ (776)
Other comprehensive income before reclassifications			13	(62)
Total reclassified from AOCL			469	614
Other comprehensive income, net of tax	255	194	482	552
Ending Balance	2,896	479	2,896	479
Recognition of previously deferred postretirement benefit plan amounts	227	300	454	600
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			454	600
Other comprehensive income, net of tax			454	600
Reclassification of income tax effects from tax reform				(2,396)
Ending Balance	(13,800)	(14,355)	(13,800)	(14,355)
Other, net
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning Balance			(67)	20
Other comprehensive income before reclassifications			13	(62)
Total reclassified from AOCL			15	14
Other comprehensive income, net of tax			28	(48)
Reclassification of income tax effects from tax reform				(12)
Ending Balance	(39)	(40)	(39)	(40)
AOCL
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning Balance	(14,094)	(14,589)	(14,321)	(12,539)
Other comprehensive income, net of tax	255	194	482	552
Reclassification of income tax effects from tax reform				(2,408)
Ending Balance	(13,839)	(14,395)	(13,839)	(14,395)
Recognition of net actuarial losses
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Total reclassified from AOCL			574	728
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			(120)	(128)
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			$ 15	$ 14

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

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