Reverse Mortgage Interests - Unsecuritized Interest (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Reverse Mortgage Interest [Abstract]
Repurchased HECM loans (exceeds 98% of their Max Claim Amount (“MCA”))	$ 699	$ 665
HECM related receivables	180	208
Funded borrower draws not yet securitized	77	72
Real estate owned (“REO”) related receivables	16	19
Total unsecuritized interests	$ 972	$ 964

Reverse Mortgage Interest [Abstract]

No definition available.

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Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized

No definition available.

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Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized, Funded Draws Not Yet Securitized

No definition available.

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Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized, Home Equity Conversion Mortgage Receivables

No definition available.

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Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized, Real Estate Owned Related Receivables

No definition available.

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Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized, Repurchase of Home Equity Conversion Mortgages

No definition available.

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