v2.4.0.8

Financial Instruments and Fair Value (Tables) | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012
Financial Instruments and Fair Value [Abstract] |  |
Summary of Investments [Table Text Block] | The following table summarizes our investments ($ amounts in 000’s):
| December 31, 2013
| Amortized Cost |  | Unrealized Gains |  | Unrealized Losses |  | Fair Value
Corporate debt securities | 603,185 |  |  | 1,506 |  |  | (374 | ) |  | 604,317 |
Commercial paper | 69,356 |  |  | 7 |  |  | — |  |  | 69,363 |
Municipal bonds | 38,815 |  |  | 48 |  |  | (20 | ) |  | 38,843 |
Certificates of deposit and term deposits | 12,645 |  |  | 3 |  |  | — |  |  | 12,648 |
U.S. government and agency securities | 2,000 |  |  | 1 |  |  | — |  |  | 2,001 |
Total available-for-sale securities | 726,001 |  |  | 1,565 |  |  | (394 | ) |  | 727,172 |
| December 31, 2012
| Amortized Cost |  | Unrealized Gains |  | Unrealized Losses |  | Fair Value
Corporate debt securities | 529,738 |  |  | 1,814 |  |  | (161 | ) |  | 531,391 |
Commercial paper | 39,229 |  |  | 22 |  |  | (6 | ) |  | 39,245 |
Municipal bonds | 36,787 |  |  | 83 |  |  | — |  |  | 36,870 |
Certificates of deposit and term deposits | 9,099 |  |  | 6 |  |  | — |  |  | 9,105 |
Total available-for-sale securities | 614,853 |  |  | 1,925 |  |  | (167 | ) |  | 616,611 |
Schedule of Unrealized Loss on Investments [Table Text Block] | The following table shows the gross unrealized losses and the related fair values of our investments that have been in a continuous unrealized loss position ($ amounts in 000’s):
| December 31, 2013
| Less Than 12 Months |  | 12 Months or Greater |  | Total
| Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses
Corporate debt securities | 182,795 |  |  | (374 | ) |  | 500 |  |  | — |  |  | 183,295 |  |  | (374 | )
Commercial paper | 7,897 |  |  | — |  |  | — |  |  | — |  |  | 7,897 |  |  | — |
Municipal bonds | 14,736 |  |  | (20 | ) |  | — |  |  | — |  |  | 14,736 |  |  | (20 | )
Total available-for-sale securities | 205,428 |  |  | (394 | ) |  | 500 |  |  | — |  |  | 205,928 |  |  | (394 | )
| The following table shows the gross unrealized losses and the related fair values of our investments that have been in a continuous unrealized loss position ($ amounts in 000’s):
| December 31, 2012
| Less Than 12 Months |  | 12 Months or Greater |  | Total
| Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses
Corporate debt securities | 133,006 |  |  | (156 | ) |  | 5,010 |  |  | (5 | ) |  | 138,016 |  |  | (161 | )
Commercial paper | 8,464 |  |  | (6 | ) |  | — |  |  | — |  |  | 8,464 |  |  | (6 | )
Total available-for-sale securities | 141,470 |  |  | (162 | ) |  | 5,010 |  |  | (5 | ) |  | 146,480 |  |  | (167 | )
Investments Classified by Contractual Maturity Date [Table Text Block] | The contractual maturities of our investments are as follows ($ amounts in 000’s)
| December 31, 2013 |  | December 31, 2012
Due within one year | 375,497 |  |  | 290,719 |
Due within one to three years | 351,675 |  |  | 325,892 |
Total | 727,172 |  |  | 616,611 |
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] | The following table presents the fair value of our financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2013 and December 31, 2012 ($ amounts in 000’s):
| December 31, 2013 |  |  |  | December 31, 2012 |  |
| Aggregate Fair Value |  | Quoted Prices in Active Markets For Identical Assets |  | Significant Other Observable Remaining Inputs |  | Significant Other Unobservable Remaining Inputs |  | Aggregate Fair Value |  | Quoted Prices in Active Markets For Identical Assets |  | Significant Other Observable Remaining Inputs |  | Significant Other Unobservable Remaining Inputs
|  |  | (Level 1) |  | (Level 2) |  | (Level 3) |  |  |  | (Level 1) |  | (Level 2) |  | (Level 3)
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate debt securities | 604,317 |  |  | — |  |  | 604,317 |  |  | — |  |  | 531,391 |  |  | — |  |  | 531,391 |  |  | — |
Commercial paper | 71,363 |  |  | — |  |  | 71,363 |  |  | — |  |  | 41,994 |  |  | — |  |  | 41,994 |  |  | — |
Municipal bonds | 38,843 |  |  | — |  |  | 38,843 |  |  | — |  |  | 36,870 |  |  | — |  |  | 36,870 |  |  | — |
Certificates of deposit and term deposits | 12,648 |  |  | — |  |  | 12,648 |  |  | — |  |  | 9,105 |  |  | — |  |  | 9,105 |  |  | — |
Money market funds | 5,724 |  |  | 5,724 |  |  | — |  |  | — |  |  | 39,871 |  |  | 39,871 |  |  | — |  |  | — |
U.S. government and agency securities | 2,001 |  |  | — |  |  | 2,001 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Total | 734,896 |  |  | 5,724 |  |  | 729,172 |  |  | — |  |  | 659,231 |  |  | 39,871 |  |  | 619,360 |  |  | — |
Liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration | 1,850 |  |  | — |  |  | — |  |  | 1,850 |  |  | — |  |  | — |  |  | — |  |  | — |
Total | 1,850 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Reported as: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash equivalents | 7,724 |  |  |  |  |  |  |  |  | 42,620 |  |  |  |  |  |  |
Short-term investments | 375,497 |  |  |  |  |  |  |  |  | 290,719 |  |  |  |  |  |  |
Long-term investments | 351,675 |  |  |  |  |  |  |  |  | 325,892 |  |  |  |  |  |  |
Total | 734,896 |  |  |  |  |  |  |  |  | 659,231 |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Table Text Block] | The following table presents quantitative information about the inputs and valuation methodologies used for our fair value measurements classified in Level 3 of the fair value hierarchy as of December 31, 2013 ($ amounts in 000’s):
| December 31, 2013
| Fair Value |  | Valuation Technique |  | Significant Unobservable Input |  | Range
Contingent consideration | $1,850 |  | Probability Weighted Income Approach |  | Revenue (in 000's) |  | $7,000 - $12,000
|  |  |  |  | Probability of occurrence (%) |  | 40%-80%

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- Definition Tabular disclosure of quantitative information about the inputs used in the fair value measurement of liabilities. This disclosure may include, but is not limited to, the fair value of the liability, valuation technique used to measure fair value, the inputs used to measure fair value, the ranges of the inputs, and the weighted averages of the inputs. + 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 (bbb) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Tabular disclosure of maturities of an entity's investments as well as any other information pertinent to the investments. + References No definition available. + Details
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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19190-110258 + Details
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- Definition For all investments in an unrealized loss position, including those for which other-than-temporary impairments have not been recognized in earnings (including investments for which a portion of an other-than-temporary impairment has been recognized in other comprehensive income), a tabular disclosure of the aggregate related fair value of investments with unrealized losses and the aggregate amount of unrealized losses (that is, the amount by which amortized cost basis exceeds fair value). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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