Fair Value Measurements (Details 2) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Net realized (gain) loss on sale of available-for-sale securities	$ 0	$ 160
Adjusted Cost			15,318
Gross Unrealized Gains			12,361
Gross Unrealized Losses			0
Fair value of available-for-sale securities	16,304		27,679
Common Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	4,195		4,195
Gross Unrealized Gains	13,124		12,361
Gross Unrealized Losses	(1,015)		0
Fair value of available-for-sale securities	16,304		16,556
Government and government sponsored entities [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost			11,123
Gross Unrealized Gains			0
Gross Unrealized Losses			0
Fair value of available-for-sale securities			$ 11,123

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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

-Publisher FASB

-Name Accounting Standards Codification

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+ References

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

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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

+ References

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

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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