Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2017

Commitments and Contingencies Disclosure [Abstract]

Schedule of Future Minimum Rental Payments for Operating Leases

At December 31, 2017, the future minimum payments under non-cancellable operating leases and purchase obligations were as follows:

	Operating Leases (a)		Purchase Obligations (b)
2018	$	2,805	$	102,784
2019	1,674		59,302
2020	1,134		42,183
2021	648		33,870
2022	272		40,228
Thereafter	116		166,868
Total	$	6,649	$	445,235

(a) Operating leases include leases on buildings, machinery and equipment under various operating leases.

(b) Purchase obligations primarily consist of payments expected to be made on natural gas, steam energy and wood chips purchase contracts. Obligations reported in the table are estimates and may vary based on changes in actual price and volumes terms.