Transactions with Other FHLBanks (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Schedule of Other Transactions [Line Items]
Proceeds from Bonds Transferred from Other Federal Home Loan Banks	$ 0	$ 0
Payments for Bonds Transferred to Other Federal Home Loan Banks	0	0
Other FHLBanks [Member]
Schedule of Other Transactions [Line Items]
Loans Receivable, Average Outstanding Amount	7,111	3,297
Other FHLBanks [Member]
Schedule of Other Transactions [Line Items]
Short-term Debt, Average Outstanding Amount	$ 16,667	$ 0