Revenue (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Total noninterest income in-scope of Topic 606									$ 75,342	$ 71,612	$ 59,034
Loan servicing income									4,843	7,292	5,636
Securities gains, net (includes $7,659, $1,085, and $6,764 of net security gains reclassified from accumulated other comprehensive income (loss) for the years ended December 31, 2019, 2018, and 2017, respectively)									7,659	1,085	6,973
Unrealized gain on equity securities, net									525	212	0
Net gains on sale of loans held for sale									15,555	21,450	22,251
Valuation allowance on servicing rights									911	46	(21)
Income on bank owned life insurance									3,785	2,793	2,772
Other noninterest income									9,410	4,762	5,335
Total noninterest income out-of-scope of Topic 606									40,866	37,548	42,988
TOTAL NONINTEREST INCOME	$ 28,030	$ 29,400	$ 32,061	$ 26,717	$ 27,045	$ 29,765	$ 27,634	$ 24,716	116,208	109,160	102,022
Service charges and fees on deposit accounts
Disaggregation of Revenue [Line Items]
Total noninterest income in-scope of Topic 606									12,790	11,291	9,570
Overdraft fees
Disaggregation of Revenue [Line Items]
Total noninterest income in-scope of Topic 606									11,543	10,796	9,365
Customer service fees
Disaggregation of Revenue [Line Items]
Total noninterest income in-scope of Topic 606									331	330	296
Credit card fee income
Disaggregation of Revenue [Line Items]
Total noninterest income in-scope of Topic 606									15,594	11,893	7,968
Debit card income
Disaggregation of Revenue [Line Items]
Total noninterest income in-scope of Topic 606									11,899	14,396	11,984
Total service charges and fees
Disaggregation of Revenue [Line Items]
Total noninterest income in-scope of Topic 606									52,157	48,706	39,183
Trust fees
Disaggregation of Revenue [Line Items]
Total noninterest income in-scope of Topic 606									19,399	18,393	15,818
Brokerage and insurance commissions
Disaggregation of Revenue [Line Items]
Total noninterest income in-scope of Topic 606									$ 3,786	$ 4,513	$ 4,033