CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
NET INCOME (LOSS)	$ 366	$ 302	$ 1,057	$ (5,492)
Items related to employee benefit plans:
Change in net actuarial loss, net of $(12), $(13), $(37) and $(41) tax	38	41	115	126
Change in net prior service cost, net of $—, $(1), $(1) and $(2) tax	1	2	4	5
Curtailment loss, net of $(1), $— , $(1), and $— tax	3	0	3	0
Reclassification of realized loss on interest rate swaps to net income, net of $(5), $—, $(10) and $— tax	15	0	31	0
Unrealized holding gain (loss) on interest rate swaps, net of $—, $3, $28 and $17 tax	1	(11)	(87)	(54)
Foreign currency translation adjustment and other, net of $(21), $22, $(2) and $24 tax	49	(112)	(181)	(115)
Other comprehensive income (loss)	107	(80)	(115)	(38)
COMPREHENSIVE INCOME (LOSS)	$ 473	$ 222	$ 942	$ (5,530)