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Debt - Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 27, 2020	Jun. 28, 2020	Mar. 29, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total debt	$ 890,000				$ 772,101
Unamortized discount and debt issuance costs	(23,733)				(22,164)
Total debt, net of discount and debt issuance costs	866,267				749,937
Less current maturities of long-term debt	(5,961)	$ (23,044)	$ (22,969)	$ (22,894)	(22,007)
Total long-term debt, net of current	860,306	$ 584,038	$ 589,828	$ 595,598	727,930
Secured Debt \| First Term Loan
Debt Instrument [Line Items]
Total debt	890,000				506,772
Secured Debt \| Second Term Loan
Debt Instrument [Line Items]
Total debt	0				265,329
Line of Credit \| Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Total debt	$ 0				$ 0