Segment and Geographical Information - Schedule of Identifiable Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Assets Held for Sale	$ 0	$ 93,707
Total Assets	2,480,147	2,679,086
Operating Segments | High Purity Cellulose
Segment Reporting Information [Line Items]
Identifiable assets, excluding assets held for sale	1,559,073	1,643,092
Operating Segments | Forest Products
Segment Reporting Information [Line Items]
Identifiable assets, excluding assets held for sale	171,167	166,801
Operating Segments | Paperboard
Segment Reporting Information [Line Items]
Identifiable assets, excluding assets held for sale	145,030	168,458
Operating Segments | Pulp & Newsprint
Segment Reporting Information [Line Items]
Identifiable assets, excluding assets held for sale	102,959	113,055
Operating Segments | Corporate
Segment Reporting Information [Line Items]
Identifiable assets, excluding assets held for sale	$ 501,918	$ 493,973