Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation of Revenue [Line Items]
Service charges and fees	$ 18,505	$ 14,960	$ 51,735	$ 43,735
Loan servicing income	1,670	1,161	5,231	4,236
Securities gains/(losses), net (includes $145 of net security losses and $1,679 of net security gains reclassified from accumulated other comprehensive income for the three months ended September 30, 2018 and 2017, respectively, and $1,037 and $5,553 of net security gains reclassified from accumulated other comprehensive income for the nine months ended September 30, 2018 and 2017, respectively)	(145)	1,679	1,037	5,553
Unrealized gain on equity securities, net	54	0	97	0
Net gains on sale of loans held for sale	7,410	4,997	18,261	17,961
Valuation adjustment on commercial servicing rights	230	5	12	29
Income on bank owned life insurance	892	766	2,206	2,039
Other noninterest income	1,149	1,409	3,536	2,941
Total noninterest income out-of-scope of Topic 606	11,260	10,017	30,380	32,759
TOTAL NONINTEREST INCOME	29,765	24,977	82,115	76,494
Service charges and fees on deposit accounts
Disaggregation of Revenue [Line Items]
Service charges and fees	2,858	2,577	8,270	7,002
Overdraft fees
Disaggregation of Revenue [Line Items]
Service charges and fees	2,990	2,479	7,716	6,950
Customer service fees
Disaggregation of Revenue [Line Items]
Service charges and fees	101	102	266	217
Credit card fee income
Disaggregation of Revenue [Line Items]
Service charges and fees	3,062	1,994	8,443	6,212
Debit card income
Disaggregation of Revenue [Line Items]
Service charges and fees	3,883	2,985	10,349	8,908
Other service charges
Disaggregation of Revenue [Line Items]
Service charges and fees	1	1	2	2
Total service charges and fees
Disaggregation of Revenue [Line Items]
Service charges and fees	12,895	10,138	35,046	29,291
Trust fees
Disaggregation of Revenue [Line Items]
Service charges and fees	4,499	3,872	13,794	11,482
Brokerage and insurance commissions
Disaggregation of Revenue [Line Items]
Service charges and fees	$ 1,111	$ 950	$ 2,895	$ 2,962

Commercial Servicing Rights (CSR) Impairment (Recovery)

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Noninterest Income Excluding Revenue From Contract With Customer

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Earnings on or other increases in the value of the cash surrender value of bank owned life insurance policies.

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Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans and leases that were sold during the reporting period. This element refers to the gain (loss) and not to the cash proceeds of the sales. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Amount of fees and commissions from banking, advisory, brokerage, and securities underwriting activities. Activities include, but are not limited to, underwriting securities, private placements of securities, investment advisory and management services, merger and acquisition services, sale and servicing of mutual funds, and other related consulting fees.

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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