Revenue from Contracts with Customers (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]
Insurance commissions	$ 1,754	$ 1,373	$ 5,349	$ 3,079
Capital markets revenue	710	843	3,481	1,796
Loan servicing and other fees	559	548	1,720	1,570
Net gain on sale of loans	631	799	1,677	1,948
Net gain on sale of investment securities available for sale	0	72	7	73
Net gain (loss) on sale of other real estate owned (OREO)	5	0	292	(12)
Dividends on FHLB and FRB stock	375	217	1,316	649
Other operating income	3,171	1,405	10,543	3,779
Total noninterest income	18,274	15,584	57,885	43,596
Fees for wealth management services
Disaggregation of Revenue [Line Items]
Revenue	10,343	9,651	31,309	28,761
Service charges on deposit accounts
Disaggregation of Revenue [Line Items]
Revenue	726	676	2,191	1,953
Merchant Interchange Fees, Safe Deposit Box Rentals, and Rent Income
Disaggregation of Revenue [Line Items]
Revenue	595	520	1,700	1,500
Banking
Disaggregation of Revenue [Line Items]
Insurance commissions	0	0	0	0
Capital markets revenue	710	843	3,481	1,796
Loan servicing and other fees	559	548	1,720	1,570
Net gain on sale of loans	631	799	1,677	1,948
Net gain on sale of investment securities available for sale	0	72	7	73
Net gain (loss) on sale of other real estate owned (OREO)	5	0	292	(12)
Dividends on FHLB and FRB stock	375	217	1,316	649
Other operating income	3,123	1,364	10,393	3,641
Total noninterest income	6,129	4,519	21,077	11,618
Banking \| Fees for wealth management services
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Banking \| Service charges on deposit accounts
Disaggregation of Revenue [Line Items]
Revenue	726	676	2,191	1,953
Wealth Management
Disaggregation of Revenue [Line Items]
Insurance commissions	1,754	1,373	5,349	3,079
Capital markets revenue	0	0	0	0
Loan servicing and other fees	0	0	0	0
Net gain on sale of loans	0	0	0	0
Net gain on sale of investment securities available for sale	0	0	0	0
Net gain (loss) on sale of other real estate owned (OREO)	0	0	0	0
Dividends on FHLB and FRB stock	0	0	0	0
Other operating income	48	41	150	138
Total noninterest income	12,145	11,065	36,808	31,978
Wealth Management \| Fees for wealth management services
Disaggregation of Revenue [Line Items]
Revenue	10,343	9,651	31,309	28,761
Wealth Management \| Service charges on deposit accounts
Disaggregation of Revenue [Line Items]
Revenue	$ 0	$ 0	$ 0	$ 0

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

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Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans.

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. 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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The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession.

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Income from agency and brokerage operations (includes sales of annuities and supplemental contracts); service charges, commissions, and fees from the sale of insurance and related services; and management fees from separate accounts, deferred annuities, and universal life products.

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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 of revenue earned, classified as other, excluding interest income.

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Amount of realized and unrealized gain (loss) resulting from the difference between acquisition price and selling price or fair value of trading assets and trading liabilities, and from the firm's direct investment activity, conducted separately from customer trading activities, including, but not limited to, investments in private equity, alternative investment products, real estate, and exchanges and memberships.

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Amount, including 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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