Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue:
Royalty revenue from a related party, net of amortization for capitalized fees paid to a related party of $11,066, $743 and $0 in 2014, 2013 and 2012	$ 7,351thrx_RoyaltyRevenueFromRelatedPartyNet	$ 1,202thrx_RoyaltyRevenueFromRelatedPartyNet	$ 0thrx_RoyaltyRevenueFromRelatedPartyNet
Revenue from collaborative arrangements from a related party, net	1,082thrx_CollaborativeArrangementsRevenue	3,330thrx_CollaborativeArrangementsRevenue	5,613thrx_CollaborativeArrangementsRevenue
Total net revenue	8,433us-gaap_Revenues	4,532us-gaap_Revenues	5,613us-gaap_Revenues
Operating expenses:
Research and development	7,498us-gaap_ResearchAndDevelopmentExpense	9,038us-gaap_ResearchAndDevelopmentExpense	8,153us-gaap_ResearchAndDevelopmentExpense
General and administrative	34,864us-gaap_GeneralAndAdministrativeExpense	24,289us-gaap_GeneralAndAdministrativeExpense	22,606us-gaap_GeneralAndAdministrativeExpense
Total operating expenses	42,362us-gaap_OperatingExpenses	33,327us-gaap_OperatingExpenses	30,759us-gaap_OperatingExpenses
Loss from operations	(33,929)us-gaap_OperatingIncomeLoss	(28,795)us-gaap_OperatingIncomeLoss	(25,146)us-gaap_OperatingIncomeLoss
Other income (expense), net	(3,272)us-gaap_OtherNonoperatingIncomeExpense	6,732us-gaap_OtherNonoperatingIncomeExpense	0us-gaap_OtherNonoperatingIncomeExpense
Interest income	563us-gaap_InvestmentIncomeNet	778us-gaap_InvestmentIncomeNet	460us-gaap_InvestmentIncomeNet
Interest expense	(36,892)us-gaap_InterestExpense	(9,348)us-gaap_InterestExpense	(6,003)us-gaap_InterestExpense
Loss from continuing operations	(73,530)	(30,633)	(30,689)
Income (loss) from discontinued operations (Notes 10 and 11)	(94,934)	(140,068)	12,147
Net loss	$ (168,464)	$ (170,701)	$ (18,542)
Basic and diluted net loss per share:
Continuing operations	$ (0.66)	$ (0.30)	$ (0.34)
Discontinued operations	$ (0.84)	$ (1.37)	$ 0.14
Basic and diluted net loss per share	$ (1.50)us-gaap_EarningsPerShareBasicAndDiluted	$ (1.67)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.20)us-gaap_EarningsPerShareBasicAndDiluted
Cash dividends declared per common share	$ 0.50	$ 0.00	$ 0.00
Shares used to compute basic and diluted net loss per share	112,059	102,425	90,909

Revenue earned under collaborative arrangements from upfront payments and contingent payments.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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