CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Common Stock in Treasury
Beginning balance (in shares) at Dec. 31, 2018		585,407,107				39,092,537
Beginning balance at Dec. 31, 2018	$ 2,362	$ 6	$ 4,715	$ (2,142)	$ (36)	$ (181)
Comprehensive income
Net income (loss)	891			891
Other comprehensive income	3				3
Comprehensive income (loss)	894
Stock-based compensation	$ 12		12
Issuance of restricted stock (in shares)		236,978
Cancellation of restricted stock (in shares)		(239,571)
Performance units vested (in shares)		535,802
Treasury stock (in shares)	5,260,687					5,260,687
Treasury stock	$ (21)					$ (21)
Tax withholding - stock compensation (in shares)		(384,393)
Tax withholding – stock compensation	(1)		(1)
Ending balance (in shares) at Dec. 31, 2019		585,555,923				44,353,224
Ending balance at Dec. 31, 2019	3,246	$ 6	4,726	(1,251)	(33)	$ (202)
Comprehensive income
Net income (loss)	(3,112)			(3,112)
Other comprehensive income	(5)				(5)
Comprehensive income (loss)	(3,117)
Stock-based compensation	4		4
Issuance of common stock (in shares)		63,250,000
Issuance of common stock	152		152
Issuance of restricted stock (in shares)		311,446
Cancellation of restricted stock (in shares)		(1,274,802)
Restricted units granted (in shares)		2,697,170
Restricted units granted	3		3
Merger consideration (in shares)		69,740,848
Merger consideration	213	$ 1	212
Tax withholding - stock compensation (in shares)		(1,484,885)
Tax withholding – stock compensation	(4)		(4)
Ending balance (in shares) at Dec. 31, 2020		718,795,700				44,353,224
Ending balance at Dec. 31, 2020	497	$ 7	5,093	(4,363)	(38)	$ (202)
Comprehensive income
Net income (loss)	(25)			(25)
Other comprehensive income	13				13
Comprehensive income (loss)	(12)
Stock-based compensation	2		2
Issuance of restricted stock (in shares)		289,442
Cancellation of restricted stock (in shares)		(405)
Restricted units granted (in shares)		2,184,681
Restricted units granted	8		8
Performance units vested (in shares)		1,001,505
Performance units vested	4		4
Merger consideration (in shares)		437,164,919
Merger consideration	2,051	$ 5	2,046
Tax withholding - stock compensation (in shares)		(763,176)
Tax withholding – stock compensation	(3)		(3)
Ending balance (in shares) at Dec. 31, 2021		1,158,672,666				44,353,224
Ending balance at Dec. 31, 2021	$ 2,547	$ 12	$ 7,150	$ (4,388)	$ (25)	$ (202)