Reverse Mortgage Interests, Net - Purchase Discount Rollforward (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Net Discount for Other Interest Securitized
Balance - beginning of period	$ (56)	$ (100)
Adjustments		(2)
Utilization of purchase discounts	5	6
Accretion	17	(15)
Transfers	(10)	(1)
Balance - end of period	(44)	(112)
Net Discount for Unsecuritized Interests
Balance - beginning of period	(68)	(122)
Additions		(6)
Utilization of purchase discounts	5	22
Accretion	2	18
Transfers	(8)	(7)
Balance - end of period	(69)	(95)
Participating Interests in HMBS \| Mortgage-backed debt
Net Premium for Participating Interests in HMBS
Balance - beginning of period	10	58
Adjustments		16
Utilization of purchase discounts	0	0
Amortization	(44)	(14)
Transfers	18	8
Balance - end of period	$ (16)	$ 36

Debt Instrument, Debt Premium, Additions

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- Definition

Debt Instrument, Debt Premium, Transfer

+ References

No definition available.

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- Definition

Debt Instrument, Debt Premium, Utilization Of Purchase Discounts

+ References

No definition available.

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- Definition

Debt Premium Rollforward [Roll Forward]

+ References

No definition available.

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- Definition

Other Interest Securitized Rollforward [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Reverse Mortgage Interest, Unpaid Principal Balance, Other Interests Securitized, Purchase Discount

+ References

No definition available.

+ Details

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- Definition

Reverse Mortgage Interest, Unpaid Principal Balance, Other Interests Securitized, Purchase Discount, Accretion (Amortization)

+ References

No definition available.

+ Details

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- Definition

Reverse Mortgage Interest, Unpaid Principal Balance, Other Interests Securitized, Purchase Discount, Additions

+ References

No definition available.

+ Details

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- Definition

Reverse Mortgage Interest, Unpaid Principal Balance, Other Interests Securitized, Purchase Discount, Transfer

+ References

No definition available.

+ Details

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- Definition

Reverse Mortgage Interest, Unpaid Principal Balance, Other Interests Securitized, Purchase Discount, Utilization

+ References

No definition available.

+ Details

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- Definition

Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized, Purchase Discount

+ References

No definition available.

+ Details

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- Definition

Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized, Purchase Discount, Accretion

+ References

No definition available.

+ Details

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- Definition

Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized, Purchase Discount, Additions

+ References

No definition available.

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- Definition

Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized, Purchase Discount, Transfer

+ References

No definition available.

+ Details

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- Definition

Reverse Mortgage Interest, Unpaid Principal Balance, Unsecuritized, Purchase Discount, Utilization

+ References

No definition available.

+ Details

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- Definition

Unsecuritized Interests Rollforward [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

+ References

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-Publisher FASB
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- Definition

Amount, after accumulated amortization, of debt discount (premium).

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