Indebtedness - Summary of Unsecured Senior Notes (Details) - USD ($)	Jun. 30, 2025	Dec. 31, 2024	Aug. 01, 2024	Feb. 01, 2024
Debt Instrument [Line Items]
Unsecured senior notes, net	$ 4,902,000,000	$ 4,891,000,000
Unsecured Senior Notes
Debt Instrument [Line Items]
Unsecured senior notes principal amount	4,950,000,000	4,950,000,000
Purchase discount and unamortized debt issuance costs	(48,000,000)	(59,000,000)
Unsecured senior notes, net	4,902,000,000	4,891,000,000
Unsecured Senior Notes \| $850 face value, 5.500% interest rate payable semi-annually, due August 2028
Debt Instrument [Line Items]
Unsecured senior notes principal amount	850,000,000	850,000,000
Face value	$ 850,000,000
Debt Instrument, Interest Rate, Stated Percentage	5.50%
Unsecured Senior Notes \| $650 face value, 5.125% interest rate payable semi-annually, due December 2030
Debt Instrument [Line Items]
Unsecured senior notes principal amount	$ 650,000,000	650,000,000
Face value	$ 650,000,000
Debt Instrument, Interest Rate, Stated Percentage	5.125%
Unsecured Senior Notes \| $600 face value, 6.000% interest rate payable semi-annually, due January 2027
Debt Instrument [Line Items]
Unsecured senior notes principal amount	$ 600,000,000	600,000,000
Face value	$ 600,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.00%
Unsecured Senior Notes \| $600 face value, 5.750% interest rate payable semi-annually, due November 2031
Debt Instrument [Line Items]
Unsecured senior notes principal amount	$ 600,000,000	600,000,000
Face value	$ 600,000,000
Debt Instrument, Interest Rate, Stated Percentage	5.75%
Unsecured Senior Notes \| $550 face value, 5.000% interest rate payable semi-annually, due February 2026
Debt Instrument [Line Items]
Unsecured senior notes principal amount	$ 500,000,000	500,000,000
Face value	$ 550,000,000
Debt Instrument, Interest Rate, Stated Percentage	5.00%
Unsecured Senior Notes \| Unsecured Senior Notes, 7.125% Due February 2032
Debt Instrument [Line Items]
Unsecured senior notes principal amount	$ 1,000,000,000	1,000,000,000		$ 1,000,000,000
Face value	$ 1,000,000,000
Debt Instrument, Interest Rate, Stated Percentage	7.125%
Unsecured Senior Notes \| Unsecured Senior Notes, 6.500% Due August 2029
Debt Instrument [Line Items]
Unsecured senior notes principal amount	$ 750,000,000	$ 750,000,000	$ 750,000,000
Face value	$ 750,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.50%

Mr. Cooper Group Inc. 10-Q