Other Operating Income (Expense), Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Income and Expenses [Abstract]
Foreign currency (loss) income	$ (394)	$ 283	$ (89)
(Loss) gain on sale or disposal of property plant & equipment	(68)	85	7
Gain (loss) on foreign currency exchange and option contracts	3,438	(645)	(5,338)
Deferred payments related to prior land sales	0	8,658	0
Costs related to business combination	0	(1,316)	0
Gain on foreign currency derivatives	0	1,153	0
New Zealand JV log trading marketing fees	1,222	951	976
Miscellaneous income (expense), net	195	(83)	896
Total	$ 4,393	$ 9,086	$ (3,548)