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Investment Securities - Additional Information (Detail) (USD $)
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3 Months Ended | 12 Months Ended | |||
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Sep. 30, 2012
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Jun. 30, 2012
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Dec. 31, 2012
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Dec. 31, 2011
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Dec. 31, 2010
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| Investment Securities [Line Items] | |||||
| Investment equity security at carrying value | $ 296,000 | ||||
| Equity security other than temporary impairment charge | 176,000 | 116,000 | 292,000 | ||
| Net unrealized gain (loss) included in comprehensive income | 3,200,000 | 6,500,000 | 3,600,000 | ||
| Net realized gain (loss) on sales of investment securities | 1,396,000 | 1,635,000 | 122,000 | ||
| Recognized in earnings resulting from the sale of investment securities | 1,700,000 | 249,000 | 205,000 | ||
| Net unrealized gains on newly reclassified | 2,000,000 | ||||
| Investment securities available for sale, carrying values | $ 18,200,000 | $ 45,800,000 | |||
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Municipal Bonds [Member]
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| Investment Securities [Line Items] | |||||
| Percentage of municipal bonds | 95.00% | ||||
| X | ||||||||||
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- Definition
Available For Sale Securities Gross Unrealized Gain Losses No definition available.
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- Definition
Equity security other than temporary impairment charge. No definition available.
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- Definition
Investment equity security at carrying value. No definition available.
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- Details
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- Definition
Percentage Of Held To Maturity Securities That Were Municipal Bonds No definition available.
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- Definition
Securities available for sale at carrying value. No definition available.
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- Definition
The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Definition
Net of tax amount of unrealized holding gain (loss) before reclassification adjustments on available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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