Fair Value Measurements - Fair Values of Note Payable and Long-Term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of note payable	$ 25	$ 25
Total	$ 869	$ 868
Senior Debentures 6.900 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Interest rate	6.90%	6.90%
Fair value of senior debt	$ 29	$ 29
Senior Debentures 6.920 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Interest rate	6.92%	6.92%
Fair value of senior debt	$ 416	$ 420
Senior Notes 6.125 % Due 2034
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Interest rate	6.125%	6.125%
Fair value of senior debt	$ 399	$ 394
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of note payable	0	0
Total	0	0
Level 1 \| Senior Debentures 6.900 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of senior debt	0	0
Level 1 \| Senior Debentures 6.920 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of senior debt	0	0
Level 1 \| Senior Notes 6.125 % Due 2034
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of senior debt	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of note payable	25	25
Total	869	868
Level 2 \| Senior Debentures 6.900 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of senior debt	29	29
Level 2 \| Senior Debentures 6.920 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of senior debt	416	420
Level 2 \| Senior Notes 6.125 % Due 2034
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of senior debt	399	394
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of note payable	0	0
Total	0	0
Level 3 \| Senior Debentures 6.900 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of senior debt	0	0
Level 3 \| Senior Debentures 6.920 % Due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of senior debt	0	0
Level 3 \| Senior Notes 6.125 % Due 2034
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of senior debt	$ 0	$ 0

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Fair value portion of notes payable.

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