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.

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on available-for-sale securities.

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Fair Value - Fair Value Measurements Using Significant Unobservable Inputs (Level III) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Total net realized/unrealized gains (losses) Included in earnings:
Interest income on securities	$ 3	$ 4	$ 10	$ 11
Net realized loss on securities available for sale				(5)
Significant Unobservable Inputs (Level III) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Beginning balance January 1,	36,934	35,604	36,179	35,789
Total net realized/unrealized gains (losses) Included in earnings:
Interest income on securities	3	4	10	11
Net realized loss on securities available for sale				(5)
Included in other comprehensive income	(169)	214	579	27
Transfers in and/or out of Level III
Purchases, issuances and settlements
Purchases
Issuances
Sales
Settlements
Ending balance, September 30	$ 36,768	$ 35,822	$ 36,768	$ 35,822