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Securities - Summary of Amortized Cost and Estimated Fair Values of Securities Held for Investment (Detail) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
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Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | $ 11,986 | $ 16,416
Gross Unrealized Gains | 115 | 281
Gross Unrealized Losses | (7) | (8)
Estimated Fair Value | 12,094 | 16,689
U.S. Federal agencies [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 607 | 781
Gross Unrealized Gains | 48 | 59
Gross Unrealized Losses |  |
Estimated Fair Value | 655 | 840
States and political subdivisions [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 11,379 | 15,635
Gross Unrealized Gains | 67 | 222
Gross Unrealized Losses | (7) | (8)
Estimated Fair Value | $ 11,439 | $ 15,849

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- Definition This item represents the excess of amortized cost basis over fair value of securities in a gain position and which are categorized as held-to-maturity. + References No definition available. + Details
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- Definition This item represents the excess of amortized cost basis over fair value of securities in a loss position and which are categorized as held-to-maturity. + References No definition available. + Details
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- Definition Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.6) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Fair value of investments in debt securities classified as held-to-maturity. + References Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -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 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
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