Consolidated Obligations Interest Rate Payment Terms (Details) (Unsecured Debt [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Debt, Gross	$ 22,085,410	$ 25,573,230
Fixed Interest Rate [Member]
Debt Instrument [Line Items]
Debt, Gross	15,204,410	18,763,230
Variable Rate [Member]
Debt Instrument [Line Items]
Debt, Gross	4,171,000	4,235,000
Step Up [Member]
Debt Instrument [Line Items]
Debt, Gross	2,610,000	2,475,000
Step Down [Member]
Debt Instrument [Line Items]
Debt, Gross	$ 100,000	$ 100,000