Financial Instruments And Investments (Sale Of Securities And The Related Effects On Pre-Tax Income ) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Financial Instruments And Investments
Proceeds from sales of available-for-sale securities	$ 22,175	$ 14,701	$ 36,406	$ 34,205	$ 63,857	$ 93,328
Gross realized gains included in pre-tax income	432	129	696	526	1,200	3,851
Gross realized losses included in pre-tax income	(235)	(244)	(294)	(672)	(511)	(502)
Gross unrealized losses included in pre-tax income	(199)	(263)	(199)	(263)	(199)	(705)
Net gains (losses) in pre-tax income	(2)	(378)	203	(409)	490	2,644
Net unrealized holding gains (losses) included in accumulated other comprehensive income	416	(6,401)	2,589	(3,978)	13,232	6,480
Net gains (losses) reclassified out of accumulated other comprehensive income	2	378	(203)	409	(490)	(2,644)
Net gains (losses) in other comprehensive income	$ 418	$ (6,023)	$ 2,386	$ (3,569)	$ 12,742	$ 3,836

This item represents the change in net unrealized holding gains or losses (before reclassification adjustments) on available for sale securities that have been included in other comprehensive income, a separate component of shareholders' equity, during the period.

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- Definition

This item represents the gross unrealized losses for securities which are categorized neither as held-to-maturity nor trading securities. Such gross unrealized losses are the excess of the carrying value of the Available-for-Sales securities over their fair value as of the reporting date. Such gross unrealized losses are included in pretax income.

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- Definition

Financial Instruments and Investments

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- Definition

Net Gains Losses Of Available For Sale Securities In Pre Tax Income

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- Definition

This item represents the change in net unrealized holding gain or loss on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 21
-Subparagraph d

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 21
-Subparagraph a

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- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 21
-Subparagraph a

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 24
-Subparagraph b

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 18, 19

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- Definition

The cash inflow associated with the sale or maturity (principal being due) of securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 16
-Subparagraph a

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 18

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 15

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 16
-Subparagraph b

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