v2.4.0.8

Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
--- | --- | ---
Fair Value Measurements |  |
Amount of transfers of financial assets between Level 1 and Level 2 measures | $ 0 |
Assets: |  |
Short term investments: | 117,218 | 200,577
Total short-term investments | 117,200 |
Available-for-sale equity securities |  |
Assets: |  |
Short term investments: | 96,942 | 174,610
Recurring |  |
Assets: |  |
Total short-term investments | 117,218 |
Recurring | Available-for-sale equity securities |  |
Assets: |  |
Short term investments: | 96,942 |
Recurring | Corporate debt securities |  |
Assets: |  |
Short term investments: | 19,388 |
Recurring | Mortgage-backed debt securities |  |
Assets: |  |
Short term investments: | 210 |
Recurring | Mortgage-CMO debt securities |  |
Assets: |  |
Short term investments: | 20 |
Recurring | Asset-backed debt securities |  |
Assets: |  |
Short term investments: | 658 |
Recurring | Level 1 |  |
Assets: |  |
Total short-term investments | 96,738 |
Recurring | Level 1 | Available-for-sale equity securities |  |
Assets: |  |
Short term investments: | 96,080 |
Recurring | Level 1 | Asset-backed debt securities |  |
Assets: |  |
Short term investments: | 658 |
Recurring | Level 2 |  |
Assets: |  |
Total short-term investments | 20,480 |
Recurring | Level 2 | Available-for-sale equity securities |  |
Assets: |  |
Short term investments: | 862 |
Recurring | Level 2 | Corporate debt securities |  |
Assets: |  |
Short term investments: | 19,388 |
Recurring | Level 2 | Mortgage-backed debt securities |  |
Assets: |  |
Short term investments: | 210 |
Recurring | Level 2 | Mortgage-CMO debt securities |  |
Assets: |  |
Short term investments: | $ 20 |

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- Definition Represents the amount of transfers of assets measured on a recurring basis between Level 1 and Level 2 of the fair value hierarchy. + References No definition available. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. + References No definition available. + 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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