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Allowance for Loan Losses - Summary of Allowance for Loan Losses and Recorded Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 2,212		$ 1,763
Allowance for Loan Losses, Collectively Evaluated for Impairment	59,267		59,233
Total Allowance for Loan Losses	61,479	$ 61,409	60,996	$ 60,517	$ 59,046	$ 56,390
Portfolio Loans, Individually Evaluated for Impairment	51,299		49,506
Portfolio Loans, Collectively Evaluated for Impairment	5,981,901		5,897,142
Total Portfolio Loans	6,033,200		5,946,648
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	1,530		1,295
Allowance for Loan Losses, Collectively Evaluated for Impairment	31,306		32,412
Total Allowance for Loan Losses	32,836	34,903	33,707	31,232	30,963	27,235
Portfolio Loans, Individually Evaluated for Impairment	29,295		11,369
Portfolio Loans, Collectively Evaluated for Impairment	2,877,600		2,910,463
Total Portfolio Loans	2,906,895		2,921,832
Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	204		360
Allowance for Loan Losses, Collectively Evaluated for Impairment	13,023		11,236
Total Allowance for Loan Losses	13,227	11,996	11,596	10,874	10,472	8,966
Portfolio Loans, Individually Evaluated for Impairment	10,651		13,672
Portfolio Loans, Collectively Evaluated for Impairment	1,549,076		1,479,744
Total Portfolio Loans	1,559,727		1,493,416
Commercial construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	157		87
Allowance for Loan Losses, Collectively Evaluated for Impairment	7,097		7,896
Total Allowance for Loan Losses	7,254	6,757	7,983	11,676	10,721	13,167
Portfolio Loans, Individually Evaluated for Impairment	2,808		15,775
Portfolio Loans, Collectively Evaluated for Impairment	264,395		241,422
Total Portfolio Loans	267,203		257,197
Consumer real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	307		10
Allowance for Loan Losses, Collectively Evaluated for Impairment	6,264		6,177
Total Allowance for Loan Losses	6,571	6,178	6,187	5,241	5,418	5,479
Portfolio Loans, Individually Evaluated for Impairment	8,529		8,674
Portfolio Loans, Collectively Evaluated for Impairment	1,218,805		1,197,983
Total Portfolio Loans	1,227,334		1,206,657
Other consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	14		11
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,577		1,512
Total Allowance for Loan Losses	1,591	$ 1,575	1,523	$ 1,494	$ 1,472	$ 1,543
Portfolio Loans, Individually Evaluated for Impairment	16		16
Portfolio Loans, Collectively Evaluated for Impairment	72,025		67,530
Total Portfolio Loans	$ 72,041		$ 67,546

X

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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