Contractual Maturities of FHLB Borrowings, by Year (Detail) (USD $) In Thousands, unless otherwise specified	0 Months Ended
Dec. 31, 2014	Dec. 31, 2014
Contractual maturities of wholesale repurchase agreements and FHLB borrowings
2015	$ 0	$ 0
2016	25,000	25,000
2017	40,000	40,000
2018	0	0
2019	25,000	25,000
2020 and thereafter	50,000	50,000
Total	140,000us-gaap_LongTermDebt	140,000us-gaap_LongTermDebt
Wholesale Repurchase Agreements
Contractual maturities of wholesale repurchase agreements and FHLB borrowings
2015	0	0
2016	25,000	25,000
2018	0	0
2019	25,000	25,000
Total	50,000	50,000
Weighted average maturity (in years)	3 years 29 days
FHLB Borrowings
Contractual maturities of wholesale repurchase agreements and FHLB borrowings
2015	0	0
2017	40,000	40,000
2018	0	0
2020 and thereafter	50,000	50,000
Total	$ 90,000	$ 90,000
Weighted average maturity (in years)	4 years 4 months 21 days

Long Term Debt Maturities Repayments Of Principal After Year Four

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Weighted Average Contractual Maturity Period

+ References

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Topic 210

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-Subparagraph (SX 210.5-02.22)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

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-Section S99

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-Subparagraph (SX 210.9-03.16)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(a))

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

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-Subparagraph (SX 210.12-04.(a))

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