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Loans and Loans Held for Sale - Summary of Restructured Loans (Detail) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2016 USD ($) tdr	Jun. 30, 2015 USD ($) tdr	Jun. 30, 2016 USD ($) tdr	Jun. 30, 2015 USD ($) tdr	Dec. 31, 2015 USD ($)
Receivables [Abstract]
Loans Receivable Held-for-sale, Reconciliation to Cash Flow, Period Increase (Decrease)				$ 23,300
Gain on sale of credit card portfolio		$ 0	$ 0	$ 2,066	$ 0
Financing Receivable, Modifications [Line Items]
Threshold period of satisfactory performance for troubled debt restructuring to be restored to accruing status				6 months
Restructured loans	[1]	$ 8,193	$ 796	$ 10,771	$ 5,381
Number of troubled debt restructuring loans returned back to accruing status | tdr		0	6	0	6
Amount of troubled debt restructuring loans returned back to accruing status			$ 300		$ 300
Performing Financial Instruments
Financing Receivable, Modifications [Line Items]
Restructured loans				$ 20,598		$ 23,955
Performing Financial Instruments | Commercial and Industrial
Financing Receivable, Modifications [Line Items]
Restructured loans				6,241		6,321
Performing Financial Instruments | Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Restructured loans				4,263		6,822
Performing Financial Instruments | Commercial Construction
Financing Receivable, Modifications [Line Items]
Restructured loans				4,351		5,013
Performing Financial Instruments | Residential Mortgage
Financing Receivable, Modifications [Line Items]
Restructured loans				2,493		2,590
Performing Financial Instruments | Home Equity
Financing Receivable, Modifications [Line Items]
Restructured loans				3,225		3,184
Performing Financial Instruments | Installment and Other Consumer
Financing Receivable, Modifications [Line Items]
Restructured loans				25		25
Nonperforming Financial Instruments
Financing Receivable, Modifications [Line Items]
Restructured loans				15,028		7,659
Nonperforming Financial Instruments | Commercial and Industrial
Financing Receivable, Modifications [Line Items]
Restructured loans				2,535		1,570
Nonperforming Financial Instruments | Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Restructured loans				4,369		3,548
Nonperforming Financial Instruments | Commercial Construction
Financing Receivable, Modifications [Line Items]
Restructured loans				2,820		1,265
Nonperforming Financial Instruments | Residential Mortgage
Financing Receivable, Modifications [Line Items]
Restructured loans				4,411		665
Nonperforming Financial Instruments | Home Equity
Financing Receivable, Modifications [Line Items]
Restructured loans				882		523
Nonperforming Financial Instruments | Installment and Other Consumer
Financing Receivable, Modifications [Line Items]
Restructured loans				11		88
Financing Receivable
Financing Receivable, Modifications [Line Items]
Restructured loans				35,626		31,614
Financing Receivable | Commercial and Industrial
Financing Receivable, Modifications [Line Items]
Restructured loans				8,776		7,891
Financing Receivable | Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Restructured loans				8,632		10,370
Financing Receivable | Commercial Construction
Financing Receivable, Modifications [Line Items]
Restructured loans				7,171		6,278
Financing Receivable | Residential Mortgage
Financing Receivable, Modifications [Line Items]
Restructured loans				6,904		3,255
Financing Receivable | Home Equity
Financing Receivable, Modifications [Line Items]
Restructured loans				4,107		3,707
Financing Receivable | Installment and Other Consumer
Financing Receivable, Modifications [Line Items]
Restructured loans				$ 36		$ 113
[1] (1) Excludes loans that were fully paid off or fully charged-off by period end. The pre-modification balance represents the balance outstanding prior to modification. The post-modification balance represents the outstanding balance at period end.

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Financing Receivable Modification Post Modification Loans Removed From Nonaccrual Status

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
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