Derivative - Changes in AOCL, net of tax (Details) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 29, 2020	Sep. 29, 2020
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 351,929	$ 571,742
Amounts reclassified from AOCL	500	700
Ending balance	322,276	322,276
Accumulated Other Comprehensive Loss
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(4,804)	(435)
Ending balance	(4,841)	(4,841)
Interest rate swap agreement \| Accumulated Other Comprehensive Loss
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		0
Other comprehensive loss before reclassifications		(4,726)
Amounts reclassified from AOCL		667
Other comprehensive loss, net of tax		(4,059)
Ending balance	$ (4,059)	$ (4,059)

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

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