Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Income Taxes
Provision (benefit) for income taxes	$ 29,276	$ 442	$ 26,796	$ (3,929)
Effective income tax rate (as a percent)	221.00%	3.00%	165.80%	(10.70%)
Discrete income tax expense			$ 28,100
Gross unrecognized tax benefits	$ 2,100		2,100
Gross unrecognized tax benefits which would affect the effective tax rate if recognized	$ 1,800		1,800
Unrecognized tax benefits as a result of a lapse in the statute of limitations			300
2013 \| Norwegian
Income Taxes
Adjustment to the pricing of the intercompany transaction			$ 16,600

An adjustment for pricing of the intercompany transaction as a result of reassessment.

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

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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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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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

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