Noninterest Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Noninterest Income [Abstract]
Service charges and fees on deposit accounts									$ 28,136	$ 25,481	$ 22,414
Wealth management revenue									22,601	20,552	16,015
Electronic banking fees									23,433	19,119	13,480
Mortgage banking revenue									21,859	6,133	5,041
Other fees for customer services									4,939	4,428	3,539
Insurance commissions									1,874	1,966	1,559
Gain on sale of investment securities									129	630	0
Bank owned life insurance									1,836	646	281
Rental income									592	466	145
Gain on sale of branch offices									7,391	0	0
Gain on sale of closed branch offices and other assets									0	266	0
Gain on sale of merchant card servicing business									0	0	400
Other									9,560	529	221
Total noninterest income	$ 54,264	$ 27,770	$ 20,897	$ 19,419	$ 20,052	$ 20,215	$ 20,674	$ 19,275	$ 122,350	$ 80,216	$ 63,095