Allowance for Loan Losses - Summary of Allowance for Loan Losses and Recorded Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 37	$ 54
Allowance for Loan Losses, Collectively Evaluated for Impairment	48,110	47,857
Total Allowance for Loan Losses	48,147	47,911	$ 46,255
Portfolio Loans, Individually Evaluated for Impairment	45,650	43,977
Portfolio Loans, Collectively Evaluated for Impairment	4,981,962	3,824,769
Total Portfolio Loans	5,027,612	3,868,746
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	15,043	20,164
Total Allowance for Loan Losses	15,043	20,164	18,921
Portfolio Loans, Individually Evaluated for Impairment	12,661	19,890
Portfolio Loans, Collectively Evaluated for Impairment	2,153,942	1,662,346
Total Portfolio Loans	2,166,603	1,682,236
Commercial and Industrial
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	10,853	13,668
Total Allowance for Loan Losses	10,853	13,668	14,433
Portfolio Loans, Individually Evaluated for Impairment	14,417	9,218
Portfolio Loans, Collectively Evaluated for Impairment	1,242,413	984,920
Total Portfolio Loans	1,256,830	994,138
Commercial Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	3	0
Allowance for Loan Losses, Collectively Evaluated for Impairment	12,622	6,093
Total Allowance for Loan Losses	12,625	6,093	5,374
Portfolio Loans, Individually Evaluated for Impairment	11,498	7,605
Portfolio Loans, Collectively Evaluated for Impairment	401,946	208,543
Total Portfolio Loans	413,444	216,148
Consumer Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	32	43
Allowance for Loan Losses, Collectively Evaluated for Impairment	8,368	6,290
Total Allowance for Loan Losses	8,400	6,333	6,362
Portfolio Loans, Individually Evaluated for Impairment	6,961	7,202
Portfolio Loans, Collectively Evaluated for Impairment	1,109,835	903,455
Total Portfolio Loans	1,116,796	910,657
Other Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	2	11
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,224	1,642
Total Allowance for Loan Losses	1,226	1,653	$ 1,165
Portfolio Loans, Individually Evaluated for Impairment	113	62
Portfolio Loans, Collectively Evaluated for Impairment	73,826	65,505
Total Portfolio Loans	$ 73,939	$ 65,567

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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The balance of financing receivables 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.

+ 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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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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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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