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INCOME TAXES - DEFERRED TAXES (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Significant components of deferred tax assets |  |  |
Net operating loss carryforwards | $ 280,400,000 | $ 276,100,000 |
Research credits | 29,800,000 | 25,000,000 |
Capitalized research and development | 300,000 | 1,400,000 |
License fees | 200,000 | 300,000 |
Other - net | 11,500,000 | 9,800,000 |
Total deferred tax assets | 322,200,000 | 312,600,000 |
Valuation allowance for deferred tax assets | (322,200,000) | (312,600,000) |
Valuation allowance |  |  |
Increase (decrease) in valuation allowance | 9,600,000 | $ (2,300,000) | $ (3,300,000)
Valuation allowance for deferred tax assets related to benefits of stock option deductions | $ 6,400,000 |  |

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- Definition The amount of the valuation allowance recorded for the tax benefit that will be credited to shareholders' equity if the tax benefit subsequently becomes realizable. Examples include 1) adjustments of the opening balance of retained earnings for certain changes in accounting principle or a correction of an error; 2) gains and losses included in comprehensive income but excluded from net income; 3) expenditures that are deductible for income tax purposes that are reported as a reduction of shareholders' equity; 4) expenses for employee stock options recognized differently for financial reporting purposes and income tax purposes; 5) dividends paid on unallocated shares held by an ESOP that are charged to retained earnings and 6) deductible temporary differences that existed at the date of a quasi reorganization. + References No definition available. + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32537-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Deferred Tax Asset -URI http://asc.fasb.org/extlink&oid=6510090 + Details
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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 25 -Paragraph 20 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68052875&loc=d3e28680-109314 Reference 2: 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=65882285&loc=d3e32621-109319 Reference 3: 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=65882285&loc=d3e32632-109319 + Details
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