Income Taxes (Summary Of Differences In Taxes From Continuing Operations) (Details) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Income Taxes
Provision at statutory rate of 35%	$ 8,030,000	$ 4,290,000	$ 15,363,000	$ 8,409,000
Tax-exempt income	(2,370,000)	(2,672,000)	(4,761,000)	(5,333,000)
State income taxes	702,000	162,000	1,096,000	247,000
Interim period effective rate adjustment	(3,000)	0	(799,000)	0
Other, net	(432,000)	(46,000)	(454,000)	110,000
Income tax expense	5,927,000	1,734,000	10,445,000	3,433,000
Effective tax rate	25.80%	14.10%	23.80%	14.30%
Statutory percentage rate of provision			35.00%
Valuation allowance	$ 0	$ 0	$ 0	$ 0

INCOME TAXES

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 47

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Subparagraph 2
-Article 4

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate shall be the regular tax rate if there are alternative tax systems.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 47

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 45
-Subparagraph a, b

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- Definition

The sum of the current income tax expense (benefit) and the deferred income tax expense (benefit) pertaining to pretax income (loss) from continuing operations; income tax expense (benefit) may include interest and penalties on tax uncertainties based on the entity's accounting policy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 15, 16, 19

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 45, 46

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- Definition

The portion of the difference, between total income tax expense (benefit) as reported in the Income Statement for the period and the expected income tax expense (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 (benefit).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Subparagraph 1
-Article 4

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- Definition

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

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- Definition

The component of income tax expense representing amounts paid or payable (or refundable) which are classified as "income taxes" as determined by applying the provisions of enacted tax law to other than the taxable income (loss) from continuing operations for the period. Items affecting income taxes and required to be disclosed, but not included elsewhere, would also be designated as "Other".

+ References

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- Definition

Reflects the effects of adjustments of previously recorded tax expense, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, IRS tax settlement and unusual repatriation of foreign earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 10A, 10B, 10C

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 10
-Subparagraph b

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- Definition

The amount of the valuation allowance recorded as of the balance sheet date pertaining to the specified deferred tax asset for which an assessment was made that it is more likely than not that all or a portion of such deferred tax asset will not be realized through related deductions on future tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 43
-Subparagraph c

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