Amount of writeoff of accrued interest on financing receivable recognized by reversing interest income.

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Amount of interest income on financing receivable on nonaccrual status.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of financing receivable on nonaccrual status.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Mortgage Loans - Non-accrual Loans (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Nonaccrual [Line Items]
Recorded investment in nonaccrual loans	$ 29,484		$ 29,484		$ 36,138	$ 28,574
Total interest income recognized	107	$ 88	208	$ 257
Single-family
Financing Receivable, Nonaccrual [Line Items]
Interest income forgone	178	246	398	420
Accrued interest receivable written off through the reversal of interest income	21	45	129	132
Recorded investment in nonaccrual loans	27,264		27,264		33,985	26,505
Total interest income recognized	103	88	195	256
Single-family \| 20- and 30-year or more, amortizing fixed-rate
Financing Receivable, Nonaccrual [Line Items]
Recorded investment in nonaccrual loans	24,728		24,728		30,173	22,907
Total interest income recognized	95	75	180	221
Single-family \| 15-year or less, amortizing fixed-rate
Financing Receivable, Nonaccrual [Line Items]
Recorded investment in nonaccrual loans	596		596		945	853
Total interest income recognized	2	2	3	6
Single-family \| Other
Financing Receivable, Nonaccrual [Line Items]
Recorded investment in nonaccrual loans	1,761		1,761		2,583	2,475
Total interest income recognized	6	10	11	27
Single-family \| Adjustable-rate
Financing Receivable, Nonaccrual [Line Items]
Recorded investment in nonaccrual loans	179		179		284	270
Total interest income recognized	0	1	1	2
Multifamily
Financing Receivable, Nonaccrual [Line Items]
Interest income forgone	21	3	29	3
Accrued interest receivable written off through the reversal of interest income	0	2	1	2
Recorded investment in nonaccrual loans	2,220		2,220		$ 2,153	$ 2,069
Total interest income recognized	$ 4	$ 0	$ 13	$ 1