v2.4.0.8

Fair Value Measurements and Marketable Securities (Investments Classified by Contractual Maturity Date) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Due in one year or less, Cost	$ 29,779
Due between one and three years, Cost	5,878
Total maturities, Cost	35,657
Available-for-sale securities, Cost	50,527	69,411
Due in one year or less, Estimated Fair Value	29,789
Due between one and three years, Estimated Fair Value	5,883
Total maturities, Estimated Fair Value	35,672
Available-for-sale securities, Estimated Fair Value	48,426	82,470
Common Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Cost	14,870
Available-for-sale securities, Estimated Fair Value	$ 12,754

Amount of available-for-sale debt securities at amortized cost maturing after one year through three years.

+ References

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Amount of available-for-sale debt securities at fair value maturing after one year through three years.

+ References

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- Definition

Available-for-sale Securities, Debt Maturities, Fair Value Disclosure

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

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Amount of available-for-sale debt securities at cost, net of adjustments, which include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at fair value maturing in the next fiscal year following the latest fiscal year.

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