Segment Reporting (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) segment	Sep. 30, 2023 USD ($)
Segment Reporting Information [Line Items]
Number of reportable business segments | segment			2
Net interest income	$ 7,275	$ 7,220	$ 21,566	$ 21,041
Fee and other income	66	76	206	209
Net revenues	7,341	7,296	21,772	21,250
Investment gains (losses), net	12	8	(28)	(34)
Fair value gains (losses), net	52	795	979	1,403
Administrative expenses	(925)	(897)	(2,793)	(2,629)
Benefit (provision) for credit losses	27	652	507	1,786
TCCA fees	(862)	(860)	(2,581)	(2,571)
Credit enhancement expense	(411)	(390)	(1,235)	(1,115)
Change in expected credit enhancement recoveries	89	(128)	189	(168)
Other expenses, net	(270)	(535)	(720)	(922)
Income before federal income taxes	5,053	5,941	16,090	17,000
Provision for federal income taxes	(1,009)	(1,242)	(3,242)	(3,535)
Net income	4,044	4,699	12,848	13,465
Related Party | Treasury
Segment Reporting Information [Line Items]
TCCA fees	(862)	(860)	(2,581)	(2,571)
Business segments | Single-Family
Segment Reporting Information [Line Items]
Net interest income	6,131	6,074	18,101	17,663
Fee and other income	48	56	154	156
Net revenues	6,179	6,130	18,255	17,819
Investment gains (losses), net	9	9	(48)	(35)
Fair value gains (losses), net	(8)	742	930	1,368
Administrative expenses	(766)	(745)	(2,327)	(2,183)
Benefit (provision) for credit losses	451	736	1,334	2,201
Credit enhancement expense	(336)	(335)	(1,022)	(949)
Change in expected credit enhancement recoveries	(45)	(170)	(134)	(298)
Other expenses, net	(218)	(411)	(612)	(730)
Income before federal income taxes	4,404	5,096	13,795	14,622
Provision for federal income taxes	(890)	(1,071)	(2,819)	(3,071)
Net income	3,514	4,025	10,976	11,551
Business segments | Single-Family | Related Party | Treasury
Segment Reporting Information [Line Items]
TCCA fees	(862)	(860)	(2,581)	(2,571)
Business segments | Multifamily
Segment Reporting Information [Line Items]
Net interest income	1,144	1,146	3,465	3,378
Fee and other income	18	20	52	53
Net revenues	1,162	1,166	3,517	3,431
Investment gains (losses), net	3	(1)	20	1
Fair value gains (losses), net	60	53	49	35
Administrative expenses	(159)	(152)	(466)	(446)
Benefit (provision) for credit losses	(424)	(84)	(827)	(415)
Credit enhancement expense	(75)	(55)	(213)	(166)
Change in expected credit enhancement recoveries	134	42	323	130
Other expenses, net	(52)	(124)	(108)	(192)
Income before federal income taxes	649	845	2,295	2,378
Provision for federal income taxes	(119)	(171)	(423)	(464)
Net income	530	674	1,872	1,914
Business segments | Multifamily | Related Party | Treasury
Segment Reporting Information [Line Items]
TCCA fees	$ 0	$ 0	$ 0	$ 0