Investment Securities (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Proceeds, gains and losses realized on securities sold or called
Proceeds on securities sold	$ 29,338	$ 24,796	$ 14,458
Gross realized gains	658	1,168	562
Gross realized losses	123	1,188	33
Proceeds on securities called	7,153	2,537	1,939
Gross realized gains		8	9
Gross realized losses		4
Exchange on General Motors Securities
Proceeds, gains and losses realized on securities sold or called
Gross realized gains		$ 30	$ 344