Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Percent

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Effective Income Tax Rate Reconciliation, Tax Act 2017

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The tax year(s) being audited in connection with the income tax examination for other entities.

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Increase decrease interest and penalties.

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Liability for uncertain tax positions, total.

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Maximum decrease in income tax expense due to release in reserves.

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Minimum decrease in income tax expense due to release in reserves.

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Tax years open to examination by Internal Revenue Service

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Unrecognized tax benefit shown as a reduction to noncurrent deferred tax assets as a result of net operating loss carryforward, a similar tax loss, or a tax credit carryforward.

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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-Name Accounting Standards Codification
-Topic 250
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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 changes in the income tax rates.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount the liability recorded for the income tax examination increased or decreased in the current year/accounting period.

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Amount recognized for uncertainty in income taxes classified as noncurrent.

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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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Taxes (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
Taxes (Detail) - USD ($) $ in Thousands	Jan. 01, 2018	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017	Dec. 31, 2017
Income Tax Contingency [Line Items]
Discrete tax benefit related to Tax Act 2017		(9.00%)	0.00%	(4.00%)	0.00%
Income tax provision at federal statutory corporate tax rate		21.00%	35.00%	21.00%	35.00%
Decrease in effective tax rate		7.00%	18.00%	7.00%	18.00%
Decrease in effective tax rate for difference between deduction for tax purposes and compensation cost recognized from stock option exercises		4.00%	7.00%	5.00%	13.00%
Other discrete tax events		(2.00%)	(2.00%)	(1.00%)	(1.00%)
Increase in reserves for income taxes, net of deferred tax benefit		$ 204		$ 204
Interest and penalties included in reserve				33
Liability for uncertain tax positions		7,674		7,674
Reserve for income taxes classified as a noncurrent iability		6,646		6,646		$ 6,488
Reserve for income taxes classified an noncurrent deferred tax assets		1,028		1,028
Interest and penalties, gross		$ 773		773
Minimum decrease in income tax expense due to release in reserves				1,200
Maximum decrease in income tax expense due to release in reserves				$ 1,300
Tax years open to examination by Internal Revenue Service				2015 through 2017
Tax years open to examination by various taxing authorities for other entities				2014 through 2017
Foreign Tax Authority \| Revenue Commissioners, Ireland
Income Tax Contingency [Line Items]
Income tax provision at federal statutory corporate tax rate				12.50%
Foreign Tax Authority \| State Administration of Taxation, China
Income Tax Contingency [Line Items]
Income tax provision at federal statutory corporate tax rate				25.00%
Domestic Tax Authority
Income Tax Contingency [Line Items]
Income tax provision at federal statutory corporate tax rate				21.00%
Accounting Standards Update 2016-16
Income Tax Contingency [Line Items]
Cumulative effect on retained earnings, net of tax	$ 5,961