Consolidated Obligations (Bonds) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 91,373	$ 94,024
Due in one year or less	$ 58,106	$ 53,247
Due in one year or less, Weighted Average Interest Rate	1.81%	2.08%
Due after one year through two years	$ 16,997	$ 22,326
Due after one year through two years, Weighted Average Interest Rate	1.91%	2.50%
Due after two years through three years	$ 3,907	$ 9,478
Due after two years through three years, Weighted Average Interest Rate	2.35%	1.97%
Due after three years through four years	$ 3,083	$ 1,881
Due after three years through four years, Weighted Average Interest Rate	2.53%	2.53%
Due after four years through five years	$ 3,503	$ 2,224
Due after four years through five years, Weighted Average Interest Rate	3.03%	2.58%
Thereafter	$ 5,777	$ 4,868
Thereafter, Weighted Average Interest Rate	3.00%	3.51%
Total par value, Weighted Average Interest Rate	1.99%	2.26%
Premiums	$ 217	$ 152
Debt Instrument, Unamortized Discount	(38)	(48)
Fair value hedging adjustments	1	(356)
Total	91,553	93,772
Earlier of Contractual Maturity or Next Call Date [Member]
Debt Instrument [Line Items]
Due in one year or less	60,639	55,672
Due after one year through two years	17,643	22,696
Due after two years through three years	4,410	9,333
Due after three years through four years	2,788	1,656
Due after four years through five years	3,376	1,864
Thereafter	$ 2,517	$ 2,803