Fair Values of Financial Instruments - Schedule of Activity Related to Financial Instruments (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Fair Value Option Activity [Roll Forward]
Net gains (losses) on financial instruments held under fair value option	$ (4,361,000)	$ (12,592,000)	$ (7,026,000)	$ (40,753,000)
Consolidated Obligation Bonds Fair Value Option
Fair Value Option Activity [Roll Forward]
Balance, beginning of the period	(222,840,000)	(1,537,745,000)	(556,866,000)	(1,704,115,000)
New transactions elected for fair value option	0	0	0	(5,000,000)
Maturities and terminations	100,000,000	505,015,000	439,840,000	705,015,000
Net gains (losses) on financial instruments held under fair value option	(1,367,000)	(11,896,000)	(7,356,000)	(40,607,000)
Change in accrued interest/unaccreted balance	(53,000)	(575,000)	122,000	(494,000)
Balance, end of the period	(124,260,000)	(1,045,201,000)	(124,260,000)	(1,045,201,000)
Consolidated Obligation - Discount Notes, Fair Value Option
Fair Value Option Activity [Roll Forward]
Balance, beginning of the period	(5,358,639,000)	(565,650,000)	(577,958,000)	0
New transactions elected for fair value option	0	0	(5,295,389,000)	(562,507,000)
Maturities and terminations	5,295,389,000	0	5,857,896,000	0
Net gains (losses) on financial instruments held under fair value option	(2,994,000)	(696,000)	330,000	(146,000)
Change in accrued interest/unaccreted balance	66,244,000	(5,714,000)	15,121,000	(9,407,000)
Balance, end of the period	0	(572,060,000)	0	(572,060,000)
Advances, Fair Value Option
Fair Value Option Activity [Roll Forward]
Balance, end of the period	$ 0	$ 0	$ 0	$ 0