Income Taxes - Reconciliation of Provision for Income Taxes at Statutory Rate (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Tax benefit at federal statutory tax rate	$ (19,718)	$ (8,688)	$ (2,497)
Tax benefit at state statutory tax rate	(1,169)	(829)	(282)
Tax benefit resulting from Beneficiary Enterprise	0	0	(95)
Foreign tax rate differential	(526)	(705)	(232)
Foreign repatriation	0	0	179
Unbenefited loss of consolidated investment	2,366	2,402	1,193
Change in valuation allowance	12,407	7,400	1,373
Meals and entertainment	34	197	162
Stock-based compensation	7,160	810	497
Nondeductible expenses and other	627	190	247
Provision for income taxes	$ 1,181us-gaap_IncomeTaxExpenseBenefit	$ 777us-gaap_IncomeTaxExpenseBenefit	$ 545us-gaap_IncomeTaxExpenseBenefit

Income tax reconciliation unbenefitted loss of consolidated investment.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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