Reverse Mortgage Interests, Net - Unsecuritized Interest (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Reverse Mortgage Interest [Abstract]
Repurchased HECM loans (exceeds 98% of their Max Claim Amount (“MCA”))	$ 634	$ 789
HECM related receivables	213	250
Funded borrower draws not yet securitized	56	64
Real estate owned (“REO”) related receivables	17	14
Total unsecuritized interests	$ 920	$ 1,117

Reverse Mortgage Interest [Abstract]

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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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