Transactions with Stockholders (Concentrations) (Details) (USD $)	Mar. 31, 2013	Dec. 31, 2012
Concentration Risk [Line Items]
Advances	$ 58,282,314,000	$ 53,943,961,000
Capital Stock Ownership By Third Party [Member]
Concentration Risk [Line Items]
Regulatory Capital Stock, Value	2,326,000,000	1,858,000,000
Concentration Risk, Percentage	51.00%	43.00%
Advances to Members and Former Members [Member]
Concentration Risk [Line Items]
Advances	43,067,000,000	35,318,000,000
Mortgage Purchase Program [Member]
Concentration Risk [Line Items]
Federal Home Loan Bank, Mortgage Purchase Program, Unpaid Principal Balance	57,000,000	61,000,000
JPMorgan Chase Bank National Association [Member] | Capital Stock Ownership By Third Party [Member]
Concentration Risk [Line Items]
Regulatory Capital Stock, Value	1,333,000,000	865,000,000
Concentration Risk, Percentage	29.00%	20.00%
JPMorgan Chase Bank National Association [Member] | Advances to Members and Former Members [Member]
Concentration Risk [Line Items]
Advances	37,700,000,000	26,000,000,000
JPMorgan Chase Bank National Association [Member] | Mortgage Purchase Program [Member]
Concentration Risk [Line Items]
Federal Home Loan Bank, Mortgage Purchase Program, Unpaid Principal Balance	0	0
U.S. Bank, N.A. [Member] | Capital Stock Ownership By Third Party [Member]
Concentration Risk [Line Items]
Regulatory Capital Stock, Value	592,000,000	592,000,000
Concentration Risk, Percentage	13.00%	14.00%
U.S. Bank, N.A. [Member] | Advances to Members and Former Members [Member]
Concentration Risk [Line Items]
Advances	4,585,000,000	4,586,000,000
U.S. Bank, N.A. [Member] | Mortgage Purchase Program [Member]
Concentration Risk [Line Items]
Federal Home Loan Bank, Mortgage Purchase Program, Unpaid Principal Balance	52,000,000	55,000,000
Fifth Third Bank [Member] | Capital Stock Ownership By Third Party [Member]
Concentration Risk [Line Items]
Regulatory Capital Stock, Value	401,000,000	401,000,000
Concentration Risk, Percentage	9.00%	9.00%
Fifth Third Bank [Member] | Advances to Members and Former Members [Member]
Concentration Risk [Line Items]
Advances	782,000,000	4,732,000,000
Fifth Third Bank [Member] | Mortgage Purchase Program [Member]
Concentration Risk [Line Items]
Federal Home Loan Bank, Mortgage Purchase Program, Unpaid Principal Balance	$ 5,000,000	$ 6,000,000
Kentucky Housing Corporation, Ohio Housing Finance Agency, Tennessee Housing Development Agency [Member]
Concentration Risk [Line Items]
Number of Relationships With Non Member Affiliates	3