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Unsecured Debt, Gross

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Face (par) amount of debt instrument at time of issuance.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Indebtedness - Summary of Unsecured Senior Notes (Details) - USD ($)	9 Months Ended
	Sep. 30, 2023	Aug. 01, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Unsecured senior notes, net	$ 3,147,000,000		$ 2,673,000,000
Amortization of Debt Discount (Premium)	2,000,000
Home Point Capital Inc [Member]
Debt Instrument [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Senior Note		$ 500,000,000
Debt Instrument, Unamortized Discount		$ 32,000,000
Unsecured Senior Notes
Debt Instrument [Line Items]
Unsecured senior notes principal amount	3,200,000,000		2,700,000,000
Purchase discount(1) and unamortized debt issuance costs	(53,000,000)		(27,000,000)
Unsecured senior notes, net	3,147,000,000		2,673,000,000
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(1)
Debt Instrument [Line Items]
Unsecured senior notes principal amount	$ 500,000,000		$ 0
Face value	$ 550,000,000
Debt Instrument, Interest Rate, Stated Percentage	5.00%