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Variable Interest Entities - Schedule of Maximum Potential Exposure (Detail) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2014 | Dec. 31, 2013
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Variable Interest Entities [Abstract] |  |
Low Income Housing Limited Partnership Investments | $ 61us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount | $ 207us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount

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- Details
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- Definition The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph b -URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5728-111685 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5747-111685 + Details
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