v2.4.0.8

Financial Instruments and Fair Value , Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 Months Ended
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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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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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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 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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- Definition Amount of liability recognized arising from contingent consideration in a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 35 -Paragraph 1 -Subparagraph b -URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476 + Details
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- Definition 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. + References No definition available. + Details
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