Reverse Mortgage Interests, Net - Unsecuritized Interest (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Reverse Mortgage Interest [Abstract]
Repurchased HECM loans (exceeds 98% MCA)	$ 782	$ 789
HECM related receivables(1)	257	250
Funded borrower draws not yet securitized	64	67
Real estate owned (“REO”) related receivables	46	14
Purchase discount, net	(69)	(68)	$ (95)	$ (122)
Total unsecuritized interests	$ 1,080	$ 1,052

Reverse Mortgage Interest [Abstract]

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Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized

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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, Purchase Discount

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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