Consolidated Statements of Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Revenues	$ 141,495	$ 128,747	$ 269,391	$ 262,872
Costs and expenses:
Cost of goods sold	113,377	109,441	223,192	217,213
Selling, general and administrative expenses	13,824	11,995	26,833	24,321
Loss on sale of central Idaho timber and timberlands	48,522		48,522
Total costs and expenses	175,723	121,436	298,547	241,534
Operating income (loss)	(34,228)	7,311	(29,156)	21,338
Interest expense, net	(8,206)	(8,016)	(14,231)	(16,085)
Income (loss) before income taxes	(42,434)	(705)	(43,387)	5,253
Income tax benefit	11,196	1,416	12,306	1,114
Net income (loss)	$ (31,238)	$ 711	$ (31,081)	$ 6,367
Net income (loss) per share:
Basic (in dollars per share)	$ (0.77)	$ 0.02	$ (0.76)	$ 0.16
Diluted (in dollars per share)	(0.77)	0.02	(0.76)	0.16
Distributions per share (in dollars per share)	$ 0.375	$ 0.375	$ 0.75	$ 0.75
Weighted-average shares outstanding (in thousands):
Basic (in shares)	40,784,129	40,842,672	40,836,503	40,822,326
Diluted (in shares)	40,784,129	40,963,488	40,836,503	40,932,852