Investments In Marketable Securities (Narrative) (Details) (USD $) In Thousands, except Share data	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2011	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Investments In Marketable Securities
Dividend and interest income from marketable securities		$ 519	$ 627
Preferred Shares Sold		96,330
Common Shares Sold		381,000
Available-for-sale Securities, Gross Realized Gains	8,655	8,809
Available-for-sale Securities, Gross Unrealized Gains	$ 7,279			$ 15,330

This item represents the number of shares held as an investment which were sold during the period.

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- Definition

The number of preferred shares held as an investment which were sold during the period

+ Details

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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

+ Details

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- Definition

This item represents the gross unrealized gains for securities which are categorized neither as held-to-maturity nor trading securities. Such gross unrealized gains are the excess of the fair value of the Available-for-sale Securities over their carrying value as of the reporting date. Such gross unrealized gains are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge. All or a portion of the unrealized holding gain of an available-for-sale security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 19

+ Details

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- Definition

Interest and dividend income on all securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 14

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 2, 3
-Article 9

+ Details

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Balance Type:	credit
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- Details

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