Debt and Finance Leases - Summary of Debt (Details) - USD ($)	9 Months Ended
Sep. 28, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Debt, gross	$ 1,234,914,000
Finance lease obligation	2,896,000
Finance lease obligation		$ 3,124,000
Total debt principal payments due	1,237,810,000	1,192,727,000
Less: Debt premium, original issue discount and issuance costs, net	(4,021,000)	(4,558,000)
Total debt	1,233,789,000	1,188,169,000
Less: Current maturities of long-term debt	(21,357,000)	(15,012,000)
Long-term debt	1,212,432,000	1,173,157,000
Credit Facility \| U.S. Revolver of $100 million maturing in November 2022, $41 available, bearing interest at LIBOR plus 2.25%, interest of 4.30% at September 28, 2019
Debt Instrument [Line Items]
Borrowing capacity	100,000,000
Borrowing capacity after outstanding letters of credit	41,000,000
Debt, gross	$ 50,000,000	0
Credit Facility \| U.S. Revolver of $100 million maturing in November 2022, $41 available, bearing interest at LIBOR plus 2.25%, interest of 4.30% at September 28, 2019 \| LIBOR
Debt Instrument [Line Items]
Basis spread	2.25%
Interest rate	4.30%
Credit Facility \| Multi-currency Revolver of $150 million maturing in November 2022, $126 available, bearing interest at LIBOR plus 2.00% at September 28, 2019
Debt Instrument [Line Items]
Borrowing capacity	$ 150,000,000
Borrowing capacity after outstanding letters of credit	126,000,000
Debt, gross	$ 0	0
Credit Facility \| Multi-currency Revolver of $150 million maturing in November 2022, $126 available, bearing interest at LIBOR plus 2.00% at September 28, 2019 \| LIBOR
Debt Instrument [Line Items]
Basis spread	2.00%
Term Loan Facility \| Term A-1 Loan Facility borrowings maturing through November 2022 bearing interest at LIBOR plus 2.25%, interest rate of 4.30% at September 28, 2019
Debt Instrument [Line Items]
Interest rate	4.30%
Debt, gross	$ 160,000,000	160,000,000
Term Loan Facility \| Term A-1 Loan Facility borrowings maturing through November 2022 bearing interest at LIBOR plus 2.25%, interest rate of 4.30% at September 28, 2019 \| LIBOR
Debt Instrument [Line Items]
Basis spread	2.25%
Term Loan Facility \| Term A-2 Loan Facility borrowings maturing through November 2024 bearing interest at LIBOR plus 2.50% (after consideration of 0.60% patronage benefit), interest rate of 4.55% at September 28, 2019
Debt Instrument [Line Items]
Interest rate	4.55%
Patronage benefit	0.60%
Debt, gross	$ 438,875,000	438,875,000
Term Loan Facility \| Term A-2 Loan Facility borrowings maturing through November 2024 bearing interest at LIBOR plus 2.50% (after consideration of 0.60% patronage benefit), interest rate of 4.55% at September 28, 2019 \| LIBOR
Debt Instrument [Line Items]
Basis spread after patronage benefit	2.50%
Senior Notes \| Senior Notes due 2024 at a fixed interest rate of 5.50%
Debt Instrument [Line Items]
Fixed interest rate	5.50%
Debt, gross	$ 495,647,000	495,647,000
Loans \| Canadian dollar, fixed interest rate term loans with rates ranging from 5.50% to 6.86% and maturity dates ranging from March 2020 through April 2028, secured by certain assets of the Temiscaming plant
Debt Instrument [Line Items]
Debt, gross	85,501,000	91,304,000
Loans \| Other loans
Debt Instrument [Line Items]
Debt, gross	$ 4,891,000	$ 3,777,000
Minimum \| Loans \| Canadian dollar, fixed interest rate term loans with rates ranging from 5.50% to 6.86% and maturity dates ranging from March 2020 through April 2028, secured by certain assets of the Temiscaming plant
Debt Instrument [Line Items]
Fixed interest rate	5.50%
Maximum \| Loans \| Canadian dollar, fixed interest rate term loans with rates ranging from 5.50% to 6.86% and maturity dates ranging from March 2020 through April 2028, secured by certain assets of the Temiscaming plant
Debt Instrument [Line Items]
Fixed interest rate	6.86%

Debt Instrument, Basis Spread on Variable Rate After Cash Patronage Benefit

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Long-term Debt And Lease Obligation, Gross

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount of long-term debt and lease obligation, classified as noncurrent.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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