CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Millions	Total	COMMON STOCK	ADDITIONAL PAID-IN CAPITAL	ACCUMULATED OTHER COMPREHENSIVE LOSS	ACCUMULATED DEFICIT	ACCUMULATED DEFICIT Cumulative Effect, Period of Adoption, Adjustment
Balance at beginning of period at Dec. 31, 2019		$ 1,090	$ 21,874	$ (2,680)	$ (6,814)	$ 9
Increase (Decrease) in Stockholders' Equity
Issuance of common stock through incentive and benefit plans		7
Repurchases of common stock		0	0
Shares withheld to satisfy tax withholdings			(39)
Share-based compensation and other, net			132
Dividends declared			(837)
Other comprehensive income (loss)	$ (115)			(115)
Net income	1,057				1,057
Other					5
Balance at end of period at Sep. 30, 2020	$ 13,689	1,097	21,130	(2,795)	(5,743)
Increase (Decrease) in Stockholders' Equity
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.75
Balance at beginning of period at Jun. 30, 2020		1,097	21,376	(2,902)	(6,109)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock through incentive and benefit plans		0
Repurchases of common stock		0	0
Shares withheld to satisfy tax withholdings			(4)
Share-based compensation and other, net			33
Dividends declared			(275)
Other comprehensive income (loss)	$ 107			107
Net income	366				366
Other					0
Balance at end of period at Sep. 30, 2020	$ 13,689	1,097	21,130	(2,795)	(5,743)
Increase (Decrease) in Stockholders' Equity
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.25
Balance at beginning of period at Dec. 31, 2020	$ 11,162	1,097	20,909	(2,813)	(8,031)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock through incentive and benefit plans		8
Repurchases of common stock	(909)	(74)	(880)
Shares withheld to satisfy tax withholdings			(44)
Share-based compensation and other, net			89
Dividends declared			(839)
Other comprehensive income (loss)	236			236
Net income	1,525				1,525
Other					0
Balance at end of period at Sep. 30, 2021	$ 11,183	1,031	19,235	(2,577)	(6,506)
Increase (Decrease) in Stockholders' Equity
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.75
Balance at beginning of period at Jun. 30, 2021		1,105	20,361	(2,710)	(7,050)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock through incentive and benefit plans		0
Repurchases of common stock	$ (909)	(74)	(880)
Shares withheld to satisfy tax withholdings			(2)
Share-based compensation and other, net			25
Dividends declared			(269)
Other comprehensive income (loss)	133			133
Net income	544				544
Other					0
Balance at end of period at Sep. 30, 2021	$ 11,183	$ 1,031	$ 19,235	$ (2,577)	$ (6,506)
Increase (Decrease) in Stockholders' Equity
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.25