Income Taxes - Reconciliation of Income Tax Computed at Federal Statutory Rate to Income Before Taxes (Detail)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. Federal statutory rate	(34.00%)	(34.00%)	(34.00%)
State taxes net of federal benefit	(5.70%)	(5.50%)	(8.90%)
Permanent differences	0.00%	0.00%	0.00%
Foreign rate differential and transactional tax	(0.50%)	(0.70%)	(3.80%)
Impact of foreign tax holiday	(1.50%)	(1.80%)	(10.40%)
Valuation allowance	41.80%	26.90%
Other	0.10%	0.60%	1.10%
Effective income tax rate	0.20%	(14.50%)	(56.00%)

Effective income tax rate reconciliation permanent differences.

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

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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- Definition

Percentage 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 changes in the valuation allowance for deferred tax assets.

+ References

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Percentage 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 applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage 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 income exempt from income tax because of a tax holiday.

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