Segment Reporting (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) segment	Sep. 30, 2022 USD ($)
Segment Reporting Information [Line Items]
Number of reportable business segments | segment			2
Net interest income	$ 7,220	$ 7,124	$ 21,041	$ 22,331
Fee and other income	76	105	209	269
Net revenues	7,296	7,229	21,250	22,600
Investment gains (losses), net	8	(172)	(34)	(323)
Fair value gains, net	795	292	1,403	1,301
Administrative expenses	(897)	(870)	(2,629)	(2,473)
Benefit (provision) for credit losses	652	(2,536)	1,786	(2,994)
TCCA fees	(860)	(850)	(2,571)	(2,515)
Credit enhancement expense	(390)	(364)	(1,115)	(974)
Change in expected credit enhancement recoveries	(128)	290	(168)	303
Other expenses, net	(535)	(154)	(922)	(612)
Income before federal income taxes	5,941	2,865	17,000	14,313
Provision for federal income taxes	(1,242)	(429)	(3,535)	(2,816)
Net income	4,699	2,436	13,465	11,497
US Treasury
Segment Reporting Information [Line Items]
TCCA fees	(860)	(850)	(2,571)	(2,515)
Business segments | Single-Family
Segment Reporting Information [Line Items]
Net interest income	6,074	5,918	17,663	18,746
Fee and other income	56	83	156	204
Net revenues	6,130	6,001	17,819	18,950
Investment gains (losses), net	9	(178)	(35)	(271)
Fair value gains, net	742	309	1,368	1,379
Administrative expenses	(745)	(730)	(2,183)	(2,084)
Benefit (provision) for credit losses	736	(2,361)	2,201	(2,837)
Credit enhancement expense	(335)	(298)	(949)	(778)
Change in expected credit enhancement recoveries	(170)	245	(298)	271
Other expenses, net	(411)	(165)	(730)	(553)
Income before federal income taxes	5,096	1,973	14,622	11,562
Provision for federal income taxes	(1,071)	(276)	(3,071)	(2,270)
Net income	4,025	1,697	11,551	9,292
Business segments | Single-Family | US Treasury
Segment Reporting Information [Line Items]
TCCA fees	(860)	(850)	(2,571)	(2,515)
Business segments | Multifamily
Segment Reporting Information [Line Items]
Net interest income	1,146	1,206	3,378	3,585
Fee and other income	20	22	53	65
Net revenues	1,166	1,228	3,431	3,650
Investment gains (losses), net	(1)	6	1	(52)
Fair value gains, net	53	(17)	35	(78)
Administrative expenses	(152)	(140)	(446)	(389)
Benefit (provision) for credit losses	(84)	(175)	(415)	(157)
Credit enhancement expense	(55)	(66)	(166)	(196)
Change in expected credit enhancement recoveries	42	45	130	32
Other expenses, net	(124)	11	(192)	(59)
Income before federal income taxes	845	892	2,378	2,751
Provision for federal income taxes	(171)	(153)	(464)	(546)
Net income	674	739	1,914	2,205
Business segments | Multifamily | US Treasury
Segment Reporting Information [Line Items]
TCCA fees	$ 0	$ 0	$ 0	$ 0