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Unearned ESOP Shares (Detail) - USD ($) $ in Millions | 12 Months Ended |
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Dec. 31, 2012 | Dec. 31, 2011
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |  |
Minimum years for eligibility to participate in ESOP | 1 year |
Borrowed funds |  | $ 1.6

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- Definition Employee Stock Ownership Plan (ESOP), Eligibility, Minimum Years of Service Required + References No definition available. + Details
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- Definition Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13,16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- References No definition available. + Details
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