Accumulated Other Comprehensive Loss - Changes in AOCI (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 28, 2020	Mar. 30, 2019
Changes in accumulated other comprehensive income (loss)
Beginning balance	$ 812,542	$ 900,049
Net current period other comprehensive income (loss)	(14,053)	1,620
Ending balance	796,287	877,119
Defined Benefit Pension Plan Items
Changes in accumulated other comprehensive income (loss)
Beginning balance	(24,761)
Amounts reclassified from AOCL	296
Net current period other comprehensive income (loss)	296
Ending balance	(24,465)
Foreign Currency Translation Adjustments
Changes in accumulated other comprehensive income (loss)
Beginning balance	(7,133)
Other comprehensive income (loss) before reclassifications	(14,349)
Net current period other comprehensive income (loss)	(14,349)
Ending balance	(21,482)
Accumulated Other Comprehensive Loss
Changes in accumulated other comprehensive income (loss)
Beginning balance	(31,894)	(23,502)
Other comprehensive income (loss) before reclassifications	(14,349)
Amounts reclassified from AOCL	296
Net current period other comprehensive income (loss)	(14,053)
Ending balance	$ (45,947)	$ (21,882)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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