Consolidated Statements Of Comprehensive Earnings (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Consolidated Statements Of Comprehensive Earnings [Abstract]
Net earnings	$ 18,087	$ 16,229	$ 50,902	$ 44,144
OTHER ITEMS OF COMPREHENSIVE EARNINGS:
Change in unrealized gain on investment securities available-for-sale, before income taxes	16,588	16,201	42,774	17,447
Reclassification adjustment for realized gains on investment securities included in net earnings, before income tax	(67)	(7)	(328)	(79)
Total other items of comprehensive earnings	16,521	16,194	42,446	17,368
Income tax expense related to other items of comprehensive earnings	(5,782)	(5,668)	(14,856)	(6,079)
COMPREHENSIVE EARNINGS	$ 28,826	$ 26,755	$ 78,492	$ 55,433

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 reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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+ Details

- Definition

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

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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

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

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- 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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