Borrowings and Other Debt Obligations - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Oct. 27, 2021 USD ($)	Sep. 30, 2021 USD ($)
Short-term Debt [Line Items]
Letters of credit outstanding, amount		$ 397	$ 382
Performance Letters of Credit
Short-term Debt [Line Items]
Letters of credit outstanding, amount		277	279
Financial Letters of Credit
Short-term Debt [Line Items]
Letters of credit outstanding, amount		6	12
Uncommitted Letters of Credit
Short-term Debt [Line Items]
Letters of credit outstanding, amount		114	91
Letters of credit outstanding, cash collateral		48	49
Senior Notes | 2028 Senior Secured Notes
Short-term Debt [Line Items]
Stated interest rate on debt						6.50%
Face amount of debt						$ 500
Redemption of debt	$ 167
Unpaid principal balance				$ 248
Senior Notes | Senior Notes 8.625 Percent Due 2030
Short-term Debt [Line Items]
Stated interest rate on debt					8.625%
Face amount of debt					$ 1,600
Debt Instrument, Repurchased Face Amount		34
Unpaid principal balance		1,560	1,600
Unamortized deferred issuance cost		11	11
Line of Credit
Short-term Debt [Line Items]
Borrowings outstanding		0	0
Line of Credit | Amended LC Credit Agreement
Short-term Debt [Line Items]
Credit agreement, maximum capacity		720	$ 720
Credit Agreement Minimum Liquidity Requirement		250
Credit Agreement Minimum Liquidity Requirement, Increase Limit		$ 400
Debt instrument, covenant, minimum interest coverage ratio		2.50
Debt Instrument, Covenant, Maximum Net Leverage Ratio		3.50
Debt Instrument, Covenant, Maximum Secured Net Leverage Ratio		1.50