Non-Operating Income (Schedule Of Non-Operating Income) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Non-Operating Income
Dividend income	$ 1,020	$ 1,132	$ 2,156	$ 2,263
Interest income	47	9	70	67
Net realized gains on sales of marketable securities	8,655		8,809	0
Other revenue	68	144	167	387
Total	$ 9,790	$ 1,285	$ 11,202	$ 2,717

Income derived from investments in equity securities representing a distribution of earnings to shareholders by the investee companies.

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 03
-Paragraph 7
-Article 5

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- Definition

Income derived from investments in debt securities and on cash and cash equivalents the earnings of which reflect the time value of money or transactions in which the payments are for the use or forbearance of money.

+ References

+ Details

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- Definition

This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity. Additionally, this item would include any losses recognized for other than temporary impairments of the subject investments in debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 16

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- Details

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- Definition

The aggregate amount of other income amounts resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) profits on securities (net of losses), and (d) miscellaneous other income items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 7
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Audit and Accounting Guide (AAG)
-Number AAG-BRD
-Chapter 4
-Paragraph 80
-Subparagraph Exhibit 4-4
-IssueDate 2006-05-01

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- Definition

The net amount of other nonoperating income and expense, which does not qualify for separate disclosure on the income statement under materiality guidelines.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 9
-Article 5

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