Taxes - Reconciliation of United States Federal Statutory Corporate Tax Rate to Company's Effective Tax Rate, or Income Tax Provision (Detail)	3 Months Ended
Apr. 01, 2018	Apr. 02, 2017
Income Tax Disclosure [Abstract]
Income tax provision at federal statutory corporate tax rate	21.00%	35.00%
State income taxes, net of federal benefit	1.00%	1.00%
Foreign tax rate differential	(7.00%)	(18.00%)
Tax credit	(1.00%)	(1.00%)
Discrete tax benefit related to stock option exercises	13.00%	33.00%
Other discrete tax events	0.00%	(1.00%)
Other	1.00%	1.00%
Income tax provision	2.00%	(16.00%)

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

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 13
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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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