Condensed Consolidated Statements of Comprehensive Income (unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Condensed Consolidated Statements of Comprehensive Income (unaudited) [Abstract]
Net income	$ 4,773	$ 4,076
Investment securities available for sale:
Unrealized gains (losses) arising in period	25	(27)
Reclassification adjustment for net gains realized in earnings	(342)	0
Other comprehensive loss before tax	(317)	(27)
Income tax benefit	110	9
Other comprehensive loss, net	(207)	(18)
Total comprehensive income	$ 4,566	$ 4,058

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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-Glossary Other Comprehensive Income

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+ Details

- Definition

This element represents Other Comprehensive Income or Loss, Before Tax, for the period. The pretax revenues, expenses, gains, and losses that under generally accepted accounting principles are included in comprehensive income, but excluded from net income. Includes the entity's proportionate share of an investee's equity adjustments for other comprehensive income. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References+ Details

- Definition

This element represents Other Comprehensive Income or Loss, Net of Tax, for the period. Includes deferred gains or losses on qualifying hedges, unrealized holding gains or losses on available-for-sale securities, minimum pension liability, and cumulative translation adjustment. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

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+ Details

- Definition

Tax effect of the change in accumulated other comprehensive income (loss), that is, the tax effect on items included in other comprehensive income (loss) during the period.

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- Definition

Pre tax reclassification adjustment for gains or losses realized upon the sale of securities.

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+ Details

- Definition

Gross appreciation or the gross loss in value of the total of unsold available-for-sale securities during the period being reported (except when designated as a fair value hedge).

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