Noninterest Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Noninterest Income [Abstract]
Service charges and fees on deposit accounts									$ 21,939	$ 19,581	$ 18,452
Wealth management revenue									13,989	11,763	11,104
Electronic banking fees									12,213	9,793	9,127
Mortgage banking revenue									5,336	6,597	3,881
Other fees for customer services									3,288	2,598	2,451
Insurance commissions									1,650	1,836	1,413
Gain on sale of investment securities									1,133	34	0
Gain on sale of merchant card services									0	1,280	0
Other									861	1,202	462
Total Noninterest Income	$ 13,578	$ 14,644	$ 15,948	$ 16,239	$ 14,696	$ 12,719	$ 13,944	$ 13,325	$ 60,409	$ 54,684	$ 46,890