v2.4.0.8

Financial Instruments and Fair Value , Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified																																													12 Months Ended
	Dec. 31, 2013 Estimate of Fair Value [Member] Recurring [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Recurring [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Recurring [Member] Level 1 [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Recurring [Member] Level 1 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Recurring [Member] Level 3 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] U.S. government and agency securities [Member] Recurring [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] U.S. government and agency securities [Member] Recurring [Member] Level 1 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] U.S. government and agency securities [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Corporate debt securities [Member] Recurring [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Corporate debt securities [Member] Recurring [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Corporate debt securities [Member] Recurring [Member] Level 1 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Corporate debt securities [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Corporate debt securities [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Commercial paper [Member] Recurring [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Commercial paper [Member] Recurring [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Commercial paper [Member] Recurring [Member] Level 1 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Commercial paper [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Commercial paper [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Municipal bonds [Member] Recurring [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Municipal bonds [Member] Recurring [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Municipal bonds [Member] Recurring [Member] Level 1 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Municipal bonds [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Municipal bonds [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Certificates of deposit and term deposits [Member] Recurring [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Certificates of deposit and term deposits [Member] Recurring [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Certificates of deposit and term deposits [Member] Recurring [Member] Level 1 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Certificates of deposit and term deposits [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Certificates of deposit and term deposits [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Money market funds [Member] Recurring [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Money market funds [Member] Recurring [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Money market funds [Member] Recurring [Member] Level 1 [Member]	Dec. 31, 2012 Estimate of Fair Value [Member] Money market funds [Member] Recurring [Member] Level 1 [Member]	Dec. 31, 2013 Estimate of Fair Value [Member] Money market funds [Member] Recurring [Member] Level 2 [Member]	Dec. 31, 2013 Reported as [Member] Recurring [Member]	Dec. 31, 2012 Reported as [Member] Recurring [Member]	Dec. 31, 2013 Reported as [Member] Recurring [Member] Cash equivalents [Member]	Dec. 31, 2012 Reported as [Member] Recurring [Member] Cash equivalents [Member]	Dec. 31, 2013 Reported as [Member] Recurring [Member] Short-term investments [Member]	Dec. 31, 2012 Reported as [Member] Recurring [Member] Short-term investments [Member]	Dec. 31, 2013 Reported as [Member] Recurring [Member] Long-term investments [Member]	Dec. 31, 2012 Reported as [Member] Recurring [Member] Long-term investments [Member]	Dec. 31, 2013 Income Approach Valuation Technique [Member] Estimate of Fair Value [Member] Recurring [Member] Level 3 [Member]	Dec. 31, 2013 Contingent Liability [Member] Minimum [Member] Income Approach Valuation Technique [Member] Level 3 [Member]	Dec. 31, 2013 Contingent Liability [Member] Maximum [Member] Income Approach Valuation Technique [Member] Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure								$ 2,001	$ 0	$ 2,001	$ 604,317	$ 531,391	$ 0	$ 604,317	$ 531,391	$ 71,363	$ 41,994	$ 0	$ 71,363	$ 41,994	$ 38,843	$ 36,870	$ 0	$ 38,843	$ 36,870	$ 12,648	$ 9,105	$ 0	$ 12,648	$ 9,105	$ 5,724	$ 39,871	$ 5,724	$ 39,871	$ 0			$ 7,724	$ 42,620	$ 375,497	$ 290,719	$ 351,675	$ 325,892
Total Assets, Fair Value Disclosure	734,896	659,231	5,724	39,871	729,172	619,360																														734,896	659,231
Contingent consideration	1,850						1,850																																					1,850
Financial Liabilities Fair Value Disclosure	1,850
Fair Value Inputs, Revenue																																													$ 7,000	$ 12,000
Fair Value Inputs, Probability of Occurrence																																													40.00%	80.00%

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

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Amount of liability recognized arising from contingent consideration in a business combination.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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