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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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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, after discount, accretion and premium amortization, of interest income and dividend income classified as other.

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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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Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Capital markets revenue									$ 4,848	$ 2,396	$ 0
Loan servicing and other fees									2,259	2,106	1,939
Net gain on sale of loans									3,283	2,441	3,048
Net gain (loss) on sale of investment securities available for sale									7	101	(77)
Net gain (loss) on sale of OREO									295	(104)	(76)
Dividends on FHLB and FRB stock									1,621	939	1,063
Other operating income									11,546	5,321	4,868
Total noninterest income	$ 18,097	$ 18,274	$ 20,075	$ 19,536	$ 15,536	$ 15,584	$ 14,785	$ 13,227	75,982	59,132	53,968
Asset Management
Disaggregation of Revenue [Line Items]
Revenue from contract with customer									42,326	38,735	36,690
Insurance Commissions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer									6,808	4,589	3,722
Deposit Account
Disaggregation of Revenue [Line Items]
Revenue from contract with customer									2,989	2,608	2,791
Merchant Interchange Fees, Safe Deposit Box Rentals, and Rent Income
Disaggregation of Revenue [Line Items]
Revenue from contract with customer									2,200	2,000	1,900
Banking
Disaggregation of Revenue [Line Items]
Capital markets revenue									4,848	2,396	0
Loan servicing and other fees									2,259	2,106	1,939
Net gain on sale of loans									3,283	2,441	3,048
Net gain (loss) on sale of investment securities available for sale									7	101	(77)
Net gain (loss) on sale of OREO									295	(104)	(76)
Dividends on FHLB and FRB stock									1,621	939	1,063
Other operating income									11,360	5,124	4,710
Total noninterest income									26,662	15,611	13,398
Banking \| Asset Management
Disaggregation of Revenue [Line Items]
Revenue from contract with customer									0	0	0
Banking \| Insurance Commissions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer									0	0	0
Banking \| Deposit Account
Disaggregation of Revenue [Line Items]
Revenue from contract with customer									2,989	2,608	2,791
Wealth Management
Disaggregation of Revenue [Line Items]
Capital markets revenue									0	0	0
Loan servicing and other fees									0	0	0
Net gain on sale of loans									0	0	0
Net gain (loss) on sale of investment securities available for sale									0	0	0
Net gain (loss) on sale of OREO									0	0	0
Dividends on FHLB and FRB stock									0	0	0
Other operating income									186	197	158
Total noninterest income									49,320	43,521	40,570
Wealth Management \| Asset Management
Disaggregation of Revenue [Line Items]
Revenue from contract with customer									42,326	38,735	36,690
Wealth Management \| Insurance Commissions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer									6,808	4,589	3,722
Wealth Management \| Deposit Account
Disaggregation of Revenue [Line Items]
Revenue from contract with customer									$ 0	$ 0	$ 0