Investments (Investments in Marketable Equity Securities) (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Investments [Abstract]
Total cost	$ 213,831	$ 169,271
Net unrealized gains	166,097	133,930
Total Fair Value	$ 379,928	$ 303,201

Equity securities categorized neither as held-to-maturity nor trading which are intended be sold within one year from the balance sheet date or the normal operating cycle, whichever is longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Research Bulletin (ARB)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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