Securities Fair Value Option Securities (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
Schedule of Fair Value Option Securities [Line Items]
Fair Value Option Securities, Fair Value	$ 175,761	$ 167,125	$ 167,860
Fair Value Option Securities, Unrealized Gain or Loss	(2,061)	(8,169)	(5,364)
U.S. agency residential mortgage-backed securities [Member]
Schedule of Fair Value Option Securities [Line Items]
Fair Value Option Securities, Fair Value	175,761	157,431	163,567
Fair Value Option Securities, Unrealized Gain or Loss	(2,061)	(8,378)	(5,365)
Other debt securities [Member]
Schedule of Fair Value Option Securities [Line Items]
Fair Value Option Securities, Fair Value	0	9,694	4,293
Fair Value Option Securities, Unrealized Gain or Loss	$ 0	$ 209	$ 1