Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term debt and finance lease obligations, gross	$ 1,287,098	$ 1,261,915
Less: unamortized senior note issuance costs	(15,259)	(15,903)
Less: finance lease liability due within one year	(7,314)	(8,467)
Long-term debt, net	$ 1,264,525	1,237,545
5.500% Senior Notes
Debt Instrument [Line Items]
Maturity	2026
Long-term debt and finance lease obligations, gross	$ 300,000	300,000
5.125% Senior Notes
Debt Instrument [Line Items]
Maturity	2029
Long-term debt and finance lease obligations, gross	$ 875,000	875,000
German Joint RCF - EUR 200 Million
Debt Instrument [Line Items]
Maturity	2023
Long-term debt and finance lease obligations, gross	$ 0	0
Canadian Joint RCF - C$160 Million
Debt Instrument [Line Items]
Maturity	2027
Long-term debt and finance lease obligations, gross	$ 54,017	0
Peace River Credit Facility - C$60 Million
Debt Instrument [Line Items]
Long-term debt and finance lease obligations, gross	0	22,874
Celgar Credit Facility - C$60.0 Million
Debt Instrument [Line Items]
Long-term debt and finance lease obligations, gross	0	0
Rosenthal Credit Facility - EUR 2.6 Million
Debt Instrument [Line Items]
Long-term debt and finance lease obligations, gross	0	0
Finance Lease Liability
Debt Instrument [Line Items]
Long-term debt and finance lease obligations, gross	$ 58,081	$ 64,041

Debt instrument maturity year.

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- Definition

Long term debt and capital lease obligations gross.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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