Debt - Long-Term Debt (Details) - USD ($) $ in Thousands	Jun. 28, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total debt	$ 628,103	$ 772,101
Unamortized discount and debt issuance costs	(15,306)	(22,164)
Total debt, net of discount and debt issuance costs	612,797	749,937
Less current maturities of long-term debt	(22,969)	(22,007)
Total long-term debt, net of current	589,828	727,930
Secured Debt \| First Term Loan
Debt Instrument [Line Items]
Total debt	499,320	506,772
Secured Debt \| Second Term Loan
Debt Instrument [Line Items]
Total debt	128,783	265,329
Line of Credit \| Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Total debt	$ 0	$ 0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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