Selected Quarterly Financial Information (Unaudited) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified
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3 Months Ended |
12 Months Ended |
Dec. 31, 2014
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Sep. 30, 2014
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Jun. 30, 2014
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Mar. 31, 2014
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Dec. 31, 2013
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Sep. 30, 2013
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Jun. 30, 2013
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Mar. 31, 2013
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Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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Quarterly Financial Information Disclosure [Abstract] |
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General and administrative expense |
$ 4,485us-gaap_GeneralAndAdministrativeExpense |
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$ 4,177us-gaap_GeneralAndAdministrativeExpense |
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$ 5,069us-gaap_GeneralAndAdministrativeExpense |
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$ 5,239us-gaap_GeneralAndAdministrativeExpense |
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$ 4,720us-gaap_GeneralAndAdministrativeExpense |
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$ 4,835us-gaap_GeneralAndAdministrativeExpense |
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$ 6,715us-gaap_GeneralAndAdministrativeExpense |
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$ 5,374us-gaap_GeneralAndAdministrativeExpense |
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$ 18,970us-gaap_GeneralAndAdministrativeExpense |
$ 21,644us-gaap_GeneralAndAdministrativeExpense |
$ 19,473us-gaap_GeneralAndAdministrativeExpense |
Operating loss |
(4,485)us-gaap_OperatingIncomeLoss |
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(4,177)us-gaap_OperatingIncomeLoss |
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(5,069)us-gaap_OperatingIncomeLoss |
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(5,239)us-gaap_OperatingIncomeLoss |
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(4,720)us-gaap_OperatingIncomeLoss |
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(4,835)us-gaap_OperatingIncomeLoss |
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(6,715)us-gaap_OperatingIncomeLoss |
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(5,374)us-gaap_OperatingIncomeLoss |
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(18,970)us-gaap_OperatingIncomeLoss |
(21,644)us-gaap_OperatingIncomeLoss |
(19,473)us-gaap_OperatingIncomeLoss |
Other income (loss), net |
77us-gaap_OtherNonoperatingIncomeExpense |
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(246)us-gaap_OtherNonoperatingIncomeExpense |
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1,452us-gaap_OtherNonoperatingIncomeExpense |
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30,374us-gaap_OtherNonoperatingIncomeExpense |
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6,574us-gaap_OtherNonoperatingIncomeExpense |
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(4,224)us-gaap_OtherNonoperatingIncomeExpense |
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(2,724)us-gaap_OtherNonoperatingIncomeExpense |
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757us-gaap_OtherNonoperatingIncomeExpense |
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31,657us-gaap_OtherNonoperatingIncomeExpense |
383us-gaap_OtherNonoperatingIncomeExpense |
9,338us-gaap_OtherNonoperatingIncomeExpense |
Interest income |
407us-gaap_InvestmentIncomeInterest |
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482us-gaap_InvestmentIncomeInterest |
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542us-gaap_InvestmentIncomeInterest |
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470us-gaap_InvestmentIncomeInterest |
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550us-gaap_InvestmentIncomeInterest |
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572us-gaap_InvestmentIncomeInterest |
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790us-gaap_InvestmentIncomeInterest |
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734us-gaap_InvestmentIncomeInterest |
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1,901us-gaap_InvestmentIncomeInterest |
2,646us-gaap_InvestmentIncomeInterest |
2,926us-gaap_InvestmentIncomeInterest |
Interest expense |
(1,107)us-gaap_InterestExpenseDebt |
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(1,103)us-gaap_InterestExpenseDebt |
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(1,098)us-gaap_InterestExpenseDebt |
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(1,094)us-gaap_InterestExpenseDebt |
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(1,083)us-gaap_InterestExpenseDebt |
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(1,077)us-gaap_InterestExpenseDebt |
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(1,074)us-gaap_InterestExpenseDebt |
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(1,069)us-gaap_InterestExpenseDebt |
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(4,402)us-gaap_InterestExpenseDebt |
(4,303)us-gaap_InterestExpenseDebt |
(5,636)us-gaap_InterestExpenseDebt |
Equity loss |
(10,006)us-gaap_IncomeLossFromEquityMethodInvestments |
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(8,962)us-gaap_IncomeLossFromEquityMethodInvestments |
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(3,175)us-gaap_IncomeLossFromEquityMethodInvestments |
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6,808us-gaap_IncomeLossFromEquityMethodInvestments |
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22,646us-gaap_IncomeLossFromEquityMethodInvestments |
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(9,866)us-gaap_IncomeLossFromEquityMethodInvestments |
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(18,400)us-gaap_IncomeLossFromEquityMethodInvestments |
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(6,987)us-gaap_IncomeLossFromEquityMethodInvestments |
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(15,335)us-gaap_IncomeLossFromEquityMethodInvestments |
(12,607)us-gaap_IncomeLossFromEquityMethodInvestments |
(26,517)us-gaap_IncomeLossFromEquityMethodInvestments |
Net loss before income taxes |
(15,114)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
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(14,006)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
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(7,348)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
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31,319us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
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23,967us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
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(19,430)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
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(28,123)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
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(11,939)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
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(5,149)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
(35,525)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
(39,362)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest |
Income tax benefit (expense) |
0us-gaap_IncomeTaxExpenseBenefit |
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0us-gaap_IncomeTaxExpenseBenefit |
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0us-gaap_IncomeTaxExpenseBenefit |
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0us-gaap_IncomeTaxExpenseBenefit |
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0us-gaap_IncomeTaxExpenseBenefit |
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0us-gaap_IncomeTaxExpenseBenefit |
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0us-gaap_IncomeTaxExpenseBenefit |
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0us-gaap_IncomeTaxExpenseBenefit |
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0us-gaap_IncomeTaxExpenseBenefit |
0us-gaap_IncomeTaxExpenseBenefit |
0us-gaap_IncomeTaxExpenseBenefit |
Net loss |
$ (15,114)us-gaap_ProfitLoss |
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$ (14,006)us-gaap_ProfitLoss |
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$ (7,348)us-gaap_ProfitLoss |
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$ 31,319us-gaap_ProfitLoss |
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$ 23,967us-gaap_ProfitLoss |
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$ (19,430)us-gaap_ProfitLoss |
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$ (28,123)us-gaap_ProfitLoss |
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$ (11,939)us-gaap_ProfitLoss |
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$ (5,149)us-gaap_ProfitLoss |
$ (35,525)us-gaap_ProfitLoss |
$ (39,362)us-gaap_ProfitLoss |
Net loss per share |
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Basic (in dollars per share) |
$ (0.73)us-gaap_EarningsPerShareBasic |
[1] |
$ (0.68)us-gaap_EarningsPerShareBasic |
[1] |
$ (0.35)us-gaap_EarningsPerShareBasic |
[1] |
$ 1.44us-gaap_EarningsPerShareBasic |
[1] |
$ 1.10us-gaap_EarningsPerShareBasic |
[1] |
$ (0.90)us-gaap_EarningsPerShareBasic |
[1] |
$ (1.33)us-gaap_EarningsPerShareBasic |
[1] |
$ (0.57)us-gaap_EarningsPerShareBasic |
[1] |
$ (0.25)us-gaap_EarningsPerShareBasic |
$ (1.66)us-gaap_EarningsPerShareBasic |
$ (1.88)us-gaap_EarningsPerShareBasic |
Diluted (in dollars per share) |
$ (0.73)us-gaap_EarningsPerShareDiluted |
[1] |
$ (0.68)us-gaap_EarningsPerShareDiluted |
[1] |
$ (0.35)us-gaap_EarningsPerShareDiluted |
[1] |
$ 1.29us-gaap_EarningsPerShareDiluted |
[1] |
$ 0.99us-gaap_EarningsPerShareDiluted |
[1] |
$ (0.90)us-gaap_EarningsPerShareDiluted |
[1] |
$ (1.33)us-gaap_EarningsPerShareDiluted |
[1] |
$ (0.57)us-gaap_EarningsPerShareDiluted |
[1] |
$ (0.25)us-gaap_EarningsPerShareDiluted |
$ (1.66)us-gaap_EarningsPerShareDiluted |
$ (1.88)us-gaap_EarningsPerShareDiluted |
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