Consolidated Obligations (Redemption Terms) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total par value	$ 77,907	$ 71,370
Total	$ 77,937	$ 71,372
Weighted Average Interest Rate [Abstract]
Within 1 year	0.51%	1.68%
After 1 year through 2 years	0.46%	1.67%
After 2 years through 3 years	1.84%	1.93%
After 3 years through 4 years	2.14%	2.74%
After 4 years through 5 years	1.82%	2.08%
After 5 years	2.71%	2.94%
Consolidated obligation bonds
Debt Instrument [Line Items]
Within 1 year	$ 62,453	$ 53,549
After 1 year through 2 years	11,690	13,853
After 2 years through 3 years	596	770
After 3 years through 4 years	165	135
After 4 years through 5 years	812	937
After 5 years	2,191	2,126
Unamortized premiums	3	1
Unamortized discounts	(9)	(10)
Valuation adjustments for hedging activities	32	9
Fair value option valuation adjustments	$ 4	$ 2
Weighted Average Interest Rate [Abstract]
Total par amount	0.59%	1.73%