Noninterest Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Noninterest Income [Abstract]
Service charges and fees on deposit accounts									$ 25,481	$ 22,414	$ 21,939
Wealth management revenue									20,552	16,015	13,989
Electronic banking fees									19,119	13,480	12,213
Mortgage banking revenue									6,133	5,041	5,336
Other fees for customer services									4,428	3,539	3,288
Insurance commissions									1,966	1,559	1,650
Gain on sale of investment securities									630	0	1,133
Bank Owned Life Insurance Income									646	281	197
Rental Income, Nonoperating									466	145	97
Gain (Loss) on Disposition of Other Assets									266	0	478
Gain on sale of merchant card services									0	400	0
Other Noninterest Income									529	221	89
Other									1,907	697	861
Total Noninterest Income	$ 20,052	$ 20,215	$ 20,674	$ 19,275	$ 18,227	$ 15,351	$ 15,801	$ 13,716	$ 80,216	$ 63,095	$ 60,409