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Securities - Amortized Cost and Fair Value of Securities with Gross Unrealized Gains and Losses (Detail) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2014 | Dec. 31, 2013
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Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | $ 308,739 | $ 324,500
Gross Unrealized Gains | 3,504 | 5,023
Gross Unrealized Losses | (4,518) | (5,014)
Estimated Market Value | 307,725 | 324,509
U.S. Treasury [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 26,009 | 26,067
Gross Unrealized Gains |  |
Gross Unrealized Losses | (780) | (795)
Estimated Market Value | 25,229 | 25,272
U.S. Government agency [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 161,535 | 174,772
Gross Unrealized Gains | 1,098 | 1,386
Gross Unrealized Losses | (2,767) | (3,186)
Estimated Market Value | 159,866 | 172,972
Mortgage-backed securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 42,478 | 44,638
Gross Unrealized Gains | 661 | 728
Gross Unrealized Losses | (324) | (574)
Estimated Market Value | 42,815 | 44,792
State and local governments [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 78,717 | 79,023
Gross Unrealized Gains | 1,745 | 2,909
Gross Unrealized Losses | (647) | (459)
Estimated Market Value | $ 79,815 | $ 81,473

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- Definition Amount of accumulated pre-tax unrealized gain before deducting pre-tax unrealized losses on investments in available-for-sale securities impacting investments. + References No definition available. + Details
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- Definition Amount of accumulated pre-tax unrealized loss before deducting pre-tax unrealized gain on investments in available-for-sale securities impacting investments. + References No definition available. + Details
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + 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 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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