(Loss) Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
(Loss) Income (numerator)
Net (loss) income	$ (915)	$ (49)	$ (1,116)	$ 8
Net (loss) income applicable to common stock for computing basic (loss) earnings per common share	(915)	(49)	(1,116)	8
Net (loss) income as adjusted for purposes of computing diluted (loss) earnings per common share	$ (915)	$ (49)	$ (1,116)	$ 8
Weighted-average number of shares:
Outstanding during period (in shares)	1,026,486	1,015,857	1,022,369	1,013,603
Non-vested restricted stock (in shares)	(31,943)	(28,618)	(29,463)	(27,556)
Weighted average shares outstanding for computing basic (loss) earnings per common share (in shares)	994,543	987,239	992,906	986,047
Incremental common shares attributable to dilutive securities:
Shares issuable under convertible securities (in shares)	0	0	0	10
Shares issuable under incentive compensation plans (in shares)	0	0	0	1,167
Number of shares as adjusted for purposes of computing diluted (loss) earnings per common share (in shares)	994,543	987,239	992,906	987,224
Basic (loss) earnings per common share (in dollars per share)	$ (0.92)	$ (0.05)	$ (1.12)	$ 0.01
Diluted (loss) earnings per common share (in dollars per share)	$ (0.92)	$ (0.05)	$ (1.12)	$ 0.01
Incentive compensation plans or convertible securities
Incremental common shares attributable to dilutive securities:
Number of shares of common stock excluded from the computation of diluted earnings per share (in shares)	7,000	1,000	9,000
Restricted stock
Incremental common shares attributable to dilutive securities:
Number of shares of common stock excluded from the computation of diluted earnings per share (in shares)	22,900	24,100	18,200	22,200