Allowance for Loan Losses - Summary of Allowance for Loan Losses and Recorded Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 798	$ 37
Allowance for Loan Losses, Collectively Evaluated for Impairment	51,977	48,110
Total Allowance for Loan Losses	52,775	48,147	$ 47,911
Portfolio Loans, Individually Evaluated for Impairment	41,935	45,650
Portfolio Loans, Collectively Evaluated for Impairment	5,569,484	4,981,962
Total Portfolio Loans	5,611,419	5,027,612
Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	0	0
Allowance for Loan Losses, Collectively Evaluated for Impairment	19,976	15,043
Total Allowance for Loan Losses	19,976	15,043	20,164
Portfolio Loans, Individually Evaluated for Impairment	16,352	12,661
Portfolio Loans, Collectively Evaluated for Impairment	2,482,124	2,153,942
Total Portfolio Loans	2,498,476	2,166,603
Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	771	0
Allowance for Loan Losses, Collectively Evaluated for Impairment	10,039	10,853
Total Allowance for Loan Losses	10,810	10,853	13,668
Portfolio Loans, Individually Evaluated for Impairment	6,866	14,417
Portfolio Loans, Collectively Evaluated for Impairment	1,394,169	1,242,413
Total Portfolio Loans	1,401,035	1,256,830
Commercial Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	0	3
Allowance for Loan Losses, Collectively Evaluated for Impairment	13,999	12,622
Total Allowance for Loan Losses	13,999	12,625	6,093
Portfolio Loans, Individually Evaluated for Impairment	6,613	11,498
Portfolio Loans, Collectively Evaluated for Impairment	449,271	401,946
Total Portfolio Loans	455,884	413,444
Consumer Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	26	32
Allowance for Loan Losses, Collectively Evaluated for Impairment	6,069	8,368
Total Allowance for Loan Losses	6,095	8,400	6,333
Portfolio Loans, Individually Evaluated for Impairment	12,079	6,961
Portfolio Loans, Collectively Evaluated for Impairment	1,178,093	1,109,835
Total Portfolio Loans	1,190,172	1,116,796
Other Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	1	2
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,894	1,224
Total Allowance for Loan Losses	1,895	1,226	$ 1,653
Portfolio Loans, Individually Evaluated for Impairment	25	113
Portfolio Loans, Collectively Evaluated for Impairment	65,827	73,826
Total Portfolio Loans	$ 65,852	$ 73,939

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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The balance of financing receivables that were collectively 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.

+ References

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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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