Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Apr. 01, 2017	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Additional Income Taxes (Textual) [Abstract]
United States statutory federal income tax rate	21.00%	35.00%		35.00%	35.00%
Deemed repatriation transition tax			$ (1,409)	$ 67,188	$ 0
Aggregate transition tax on foreign earnings resulting from the 2017 Tax Act			65,800
Excess tax benefits recognized in the provision for income taxes resulting form the adoption of new accounting standard			21,300	32,000	$ 17,200
Net deferred tax assets			220,650	215,028
Valuation allowance			$ (108,724)	$ (95,491)

Additional Income Taxes.

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- Definition

Aggregate Transition Tax on Foreign Earnings, 2017 Tax Act

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) by applying the domestic federal statutory income tax rates to pretax net income from continuing operations attributable to the transition tax on the mandatory deemed repatriation of foreign earnings resulting from the 2017 Tax Act

+ References

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- Definition

Excess Tax Benefit of Stock-Based Compensation, Component of Provision for Income Taxes

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No definition available.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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

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