Borrowed Funds - Interest Expense on Borrowings (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Banking and Thrift [Abstract]
Federal Home Loan Bank advances	$ 2,515	$ 3,986	$ 5,495
Securities sold under agreements to repurchase	78	124	201
Other borrowings	809	809	860
Net interest expense on borrowed funds	$ 3,402us-gaap_InterestExpenseBorrowings	$ 4,919us-gaap_InterestExpenseBorrowings	$ 6,556us-gaap_InterestExpenseBorrowings

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Aggregate amount of interest expense on all borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.7,8)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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- Definition

Interest expense incurred during the reporting period on long-term borrowings associated with Federal Home Loan Bank and Federal Reserve Bank advances.

+ References

No definition available.

+ Details

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- Definition

Interest expense incurred on all other long-term debt, which may include (1) interest on long-term notes, and (2) amortization of issuance costs not otherwise separately disclosed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.8)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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- Definition

Gross expenses on securities sold coupled with an agreement to repurchase the same from the same counterparty at a fixed or determinable price within a fixed or variable time period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.7)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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