Other Assets - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 8,776	$ 8,679	$ 8,478
Capitalized debt issuance costs	300	500
Capitalized Software	4,100	4,100
Pacific Northwest
Finite-Lived Intangible Assets [Line Items]
Prepaid roads	3,700	3,200
New Zealand
Finite-Lived Intangible Assets [Line Items]
Prepaid roads	$ 2,700	$ 2,200
Software Costs
Finite-Lived Intangible Assets [Line Items]
Amortization period, in years	5 years
New Zealand JV | New Zealand Timber
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 8,800