Trading Securities (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013
Schedule of Trading Securities [Line Items]
Trading Securities, Fair Value	$ 86,571,000	$ 91,616,000	$ 206,598,000
Trading Securities, Net Unrealized Gain (Loss)	136,000	11,000	239,000
Trading Securities, Pledged as Collateral	0	0	0
U.S. Government agency debentures [Member]
Schedule of Trading Securities [Line Items]
Trading Securities, Fair Value	28,588,000	34,120,000	55,358,000
Trading Securities, Net Unrealized Gain (Loss)	14,000	77,000	48,000
U.S. agency residential mortgage-backed securities [Member]
Schedule of Trading Securities [Line Items]
Trading Securities, Fair Value	23,595,000	21,011,000	33,106,000
Trading Securities, Net Unrealized Gain (Loss)	83,000	123,000	160,000
Municipal and other tax-exempt securities [Member]
Schedule of Trading Securities [Line Items]
Trading Securities, Fair Value	27,280,000	27,350,000	90,710,000
Trading Securities, Net Unrealized Gain (Loss)	58,000	(182,000)	(10,000)
Other trading securities [Member]
Schedule of Trading Securities [Line Items]
Trading Securities, Fair Value	7,108,000	9,135,000	27,424,000
Trading Securities, Net Unrealized Gain (Loss)	$ (19,000)	$ (7,000)	$ 41,000