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Allowance for Loan Losses - Summary of Allowance for Loan Losses and Recorded Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 389		$ 798
Allowance for Loan Losses, Collectively Evaluated for Impairment	54,962		51,977
Total Allowance for Loan Losses	55,351	$ 55,816	52,775	$ 52,213	$ 50,347	$ 48,147
Portfolio Loans, Individually Evaluated for Impairment	40,462		41,935
Portfolio Loans, Collectively Evaluated for Impairment	5,717,357		5,569,484
Total Portfolio Loans	5,757,819		5,611,419
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	24,358		19,976
Total Allowance for Loan Losses	24,358	20,570	19,976	15,978	15,266	15,043
Portfolio Loans, Individually Evaluated for Impairment	6,472		16,352
Portfolio Loans, Collectively Evaluated for Impairment	2,658,170		2,482,124
Total Portfolio Loans	2,664,642		2,498,476
Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	340		771
Allowance for Loan Losses, Collectively Evaluated for Impairment	8,916		10,039
Total Allowance for Loan Losses	9,256	13,244	10,810	14,771	14,740	10,853
Portfolio Loans, Individually Evaluated for Impairment	18,568		6,866
Portfolio Loans, Collectively Evaluated for Impairment	1,382,715		1,394,169
Total Portfolio Loans	1,401,283		1,401,035
Commercial Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	0
Allowance for Loan Losses, Collectively Evaluated for Impairment	13,944		13,999
Total Allowance for Loan Losses	13,944	14,102	13,999	11,701	10,825	12,625
Portfolio Loans, Individually Evaluated for Impairment	4,257		6,613
Portfolio Loans, Collectively Evaluated for Impairment	422,497		449,271
Total Portfolio Loans	426,754		455,884
Consumer Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	24		26
Allowance for Loan Losses, Collectively Evaluated for Impairment	5,779		6,069
Total Allowance for Loan Losses	5,803	5,956	6,095	8,418	8,261	8,400
Portfolio Loans, Individually Evaluated for Impairment	11,130		12,079
Portfolio Loans, Collectively Evaluated for Impairment	1,183,942		1,178,093
Total Portfolio Loans	1,195,072		1,190,172
Other Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	25		1
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,965		1,894
Total Allowance for Loan Losses	1,990	$ 1,944	1,895	$ 1,345	$ 1,255	$ 1,226
Portfolio Loans, Individually Evaluated for Impairment	35		25
Portfolio Loans, Collectively Evaluated for Impairment	70,033		65,827
Total Portfolio Loans	$ 70,068		$ 65,852

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
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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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-Publisher FASB
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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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