v2.4.0.8

Tax Effects of Temporary Differences Comprise Deferred Tax Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified | Sep. 30, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
--- | --- | --- | --- | ---
Deferred tax assets |  |  |  |
Equity securities |  | $ 4,346 | $ 1,098 |
Accrued liabilities |  | 1,910 | 915 |
Stock-based compensation |  | 363 | 178 |
Deferred revenue |  | 22,684 | 6,546 |
Research and development tax credits | 6,600 | 5,848 | 5,556 |
Net operating loss carryforwards |  | 80,159 | 70,679 |
Total deferred tax assets |  | 115,310 | 84,972 |
Less: Valuation allowance |  | 113,051 | 82,125 | 52,036
Net deferred tax assets |  | 2,259 | 2,847 |
Deferred tax liabilities |  |  |  |
Property and equipment |  | 478 | 406 |
Intangible assets |  | 1,781 | 2,441 |
Total deferred tax liabilities |  | 2,259 | 2,847 |
Net deferred tax assets (liabilities) |  |  |  |

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32621-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32632-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=29652012&loc=d3e28680-109314 + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32621-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32632-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=29652012&loc=d3e28680-109314 + Details
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