Loans and Allowance for Credit Losses - Schedule of Activity of Purchased Impaired Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Purchased impaired loans	$ 28,755	$ 33,242
Allowance for loan losses	(475)	(863)
Carrying amount, net of allowance	28,280	32,379
Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Purchased impaired loans	674	691
Allowance for loan losses	(192)	(247)
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Purchased impaired loans	24,431	28,499
Allowance for loan losses	(193)	(533)
Residential [Member]
Financing Receivable, Impaired [Line Items]
Purchased impaired loans	86	127
Allowance for loan losses	(13)	(13)
Consumer Loan [Member]
Financing Receivable, Impaired [Line Items]
Purchased impaired loans	3,564	3,925
Allowance for loan losses	$ (77)	$ (70)

Valuation allowance for noncovered loans acquired with deteriorated credit quality that are expected to be uncollectible.

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying amount, net of allowance of financing receivables that were acquired with deteriorated credit quality.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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