Provision (Benefit) for Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current
Federal	$ 74us-gaap_CurrentFederalTaxExpenseBenefit
State	79	90	61
Foreign	(14)us-gaap_CurrentForeignTaxExpenseBenefit	1us-gaap_CurrentForeignTaxExpenseBenefit	(409)us-gaap_CurrentForeignTaxExpenseBenefit
Current Income Tax Expense (Benefit), Total	139us-gaap_CurrentIncomeTaxExpenseBenefit	91us-gaap_CurrentIncomeTaxExpenseBenefit	(348)us-gaap_CurrentIncomeTaxExpenseBenefit
Deferred
Federal	168	216	(171)
State	34	87
Foreign	(293)	(251)	(62)
Deferred income taxes	(109)us-gaap_DeferredIncomeTaxExpenseBenefit	59us-gaap_DeferredIncomeTaxExpenseBenefit	(220)us-gaap_DeferredIncomeTaxExpenseBenefit
Income tax provision (benefit)	48us-gaap_IncomeTaxExpenseBenefit	143us-gaap_IncomeTaxExpenseBenefit	(581)us-gaap_IncomeTaxExpenseBenefit
Deferred Income Taxes
Deferred
Deferred income taxes	$ (91)	$ 52	$ (233)

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