v2.4.0.8

Fair Value of Financial Instruments (Cash and Cash Equivalents, Available-for-sale Securities, Restricted Cash Reconciliation) (Details) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
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Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | $ 132,766 | $ 118,424
Unrealized Gains | 45 | 8
Unrealized Losses | (7) | 0
Fair value | 132,804 | 118,432
Cash and Cash Equivalents |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Cash and cash equivalents | 27,488 | 23,419
Amortized cost, total | 42,368 | 34,883
Unrealized Gains | 1 | 2
Unrealized Losses | 0 | 0
Fair value | 42,369 | 34,885
Short-term Investments |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 54,810 | 83,541
Unrealized Gains | 17 | 6
Unrealized Losses | 0 | 0
Fair value | 54,827 | 83,547
Long-Term Investments |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 35,588 |
Unrealized Gains | 27 |
Unrealized Losses | (7) |
Fair value | 35,608 |
Money market funds |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Money market funds | Cash and Cash Equivalents |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 183 | 170
Fair value | 183 | 170
Commercial paper | Cash and Cash Equivalents |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 14,697 | 11,294
Unrealized Gains | 1 | 2
Unrealized Losses | 0 | 0
Fair value | 14,698 | 11,296
Commercial paper | Short-term Investments |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 32,784 | 21,078
Unrealized Gains | 6 | 2
Unrealized Losses | 0 | 0
Fair value | 32,790 | 21,080
Corporate bonds | Short-term Investments |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 16,894 |
Unrealized Gains | 11 |
Unrealized Losses | 0 |
Fair value | 16,905 |
Corporate bonds | Long-Term Investments |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 15,256 |
Unrealized Gains | 22 |
Unrealized Losses | (4) |
Fair value | 15,274 |
Municipal bonds | Short-term Investments |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 1,128 |
Unrealized Gains | 0 |
Unrealized Losses | 0 |
Fair value | 1,128 |
U.S. government agencies | Short-term Investments |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 4,004 | 62,463
Unrealized Gains | 0 | 4
Unrealized Losses | 0 | 0
Fair value | 4,004 | 62,467
U.S. government agencies | Long-Term Investments |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 14,835 |
Unrealized Gains | 1 |
Unrealized Losses | (3) |
Fair value | 14,833 |
Asset-backed securities | Long-Term Investments |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Amortized cost, total | 5,497 |
Unrealized Gains | 4 |
Unrealized Losses | 0 |
Fair value | $ 5,501 |

X
- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References No definition available. + Details
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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References No definition available. + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer. + 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 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 + Details
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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