POSTRETIREMENT BENEFIT PLANS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 24, 2017	Sep. 30, 2018	Sep. 24, 2017
Defined Benefit Plan Disclosure [Line Items]
Recognition of previously deferred postretirement benefit plan amounts, before tax	$ 382	$ 309	$ 1,100	$ 930
Recognition of previously deferred postretirement benefit plan amounts, net of tax	300	200	900	602
Retiree medical and life insurance plans
Defined Benefit Plan Disclosure [Line Items]
Recognition of previously deferred postretirement benefit plan amounts, before tax	13	14	42	41
Qualified defined benefit pension plans
Defined Benefit Plan Disclosure [Line Items]
Material contributions to qualified defined benefit pension plans	$ 1,500	$ 0	$ 5,000	$ 0