Securities Fair Value Option Securities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013
Schedule of Fair Value Option Securities [Line Items]
Fair Value Option Securities, Fair Value	$ 160,884	$ 167,125	$ 210,192
Fair Value Option Securities, Unrealized Gain or Loss	(5,510)	(8,169)	772
U.S. agency residential mortgage-backed securities [Member]
Schedule of Fair Value Option Securities [Line Items]
Fair Value Option Securities, Fair Value	156,525	157,431	208,900
Fair Value Option Securities, Unrealized Gain or Loss	(5,794)	(8,378)	726
Other debt securities [Member]
Schedule of Fair Value Option Securities [Line Items]
Fair Value Option Securities, Fair Value	4,359	9,694	1,292
Fair Value Option Securities, Unrealized Gain or Loss	$ 284	$ 209	$ 46