Income tax holiday tax rate.

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Income Taxes [Line Items]

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A brief description of status of the tax examination, significant findings to date, and the entity's position with respect to the findings.

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Tax year being audited in the income tax examination, in CCYY format.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Line Items]
Gross Massachusetts tax research other tax credit carryforwards	$ 8,933
Tax credit expiration period	2029
Gross unrecognized tax benefits excluding interest and penalties	$ 4,332	$ 19,610	$ 47,684	$ 40,674
Net unrecognized tax benefit excluding interest and penalties that would impact effective tax rate	4,326
Net benefit to income tax expense, excluding interest and penalties, due to discrete reserve releases	7,304
Accrued interest on unrecognized tax benefits	157	578	2,159
Net unrecognized tax benefits, excluding interest and penalties, related to foreign tax positions	$ 923
Income tax examination, description	The Company is subject to examination by U.S. federal, state and foreign tax authorities. The United States Internal Revenue Service commenced an examination of our U.S. federal tax filings for tax years 2011 through 2013 during the quarter ended March 31, 2015.
Change in valuation allowance	$ (20,636)	$ (339)	$ (395)
Undistributed earnings in foreign subsidiaries	$ 450,000
Income tax holiday tax rate	9.00%	9.00%	7.00%
Other Operations [Member]
Income Taxes [Line Items]
Income tax holiday tax rate	16.00%
State and Foreign [Member]
Income Taxes [Line Items]
Operating loss carry forwards	$ 7,784
State and Foreign [Member] \| Indefinite [Member]
Income Taxes [Line Items]
Operating loss carry forwards	5,000
State and Foreign [Member] \| 2021 [Member]
Income Taxes [Line Items]
Operating loss carry forwards	$ 2,784
Earliest Tax Year [Member]
Income Taxes [Line Items]
Income tax examination period	2011
Latest Tax Year [Member]
Income Taxes [Line Items]
Income tax examination period	2013