Income Taxes (Reconciliation Of The Provision For Income Taxes) (Details) (USD $)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Tax expense computed at statutory rate	$ 20,234,000	$ 18,942,000	$ 17,266,000
State income taxes, net of federal tax benefit	2,800,000	2,572,000	2,551,000
Federal jobs credits	(4,196,000)	(1,615,000)	(881,000)
Tax exempt interest	(253,000)	(370,000)	(504,000)
Other, net	1,071,000	149,000	561,000
Tax Provision	$ 19,656,000	$ 19,678,000	$ 18,993,000

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to noncontrolling interest income or expense that is exempt from income taxes under enacted tax laws.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the year/accounting period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to state and local income tax expense or benefit.

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The sum of the differences between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to tax credits.

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