Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands		12 Months Ended
	Nov. 17, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
U.S. federal statutory income tax rate		21.00%	21.00%	35.00%
Nontaxable bargain purchase gain		0.00%	(4.20%)	(32.30%)
Change in valuation allowance		(8.60%)	0.00%	0.00%
Tax credits (excluding FTC)		3.10%	(3.00%)	(1.50%)
State credits		2.80%	0.00%	0.00%
U.S. federal rate change		0.00%	0.00%	3.20%
Difference in foreign statutory rates		2.30%	5.90%	0.00%
Global Intangible Low Taxed Income (Net of FTC)		0.00%	3.70%	0.00%
Book tax differences related to joint venture		0.00%	2.00%	0.00%
Net changes in uncertain tax positions		(1.20%)	(3.10%)	0.00%
Adjustment to previously filed tax returns		0.10%	(2.40%)	(0.10%)
Other		0.50%	1.50%	1.30%
Income tax rate as reported		20.00%	21.40%	5.60%
Business Acquisition [Line Items]
Gain on bargain purchase		$ 0	$ 20,449	$ 316,555
Change in valuation allowance for deferred tax assets		$ 16,000
Re-measurement of deferred tax assets			11,000
Tembec Inc.
Business Acquisition [Line Items]
Gain on bargain purchase	$ 317,000		$ 20,000	$ 317,000