Segment and Geographical Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011		Dec. 31, 2011
Segment Reporting Information [Line Items]
Assets	$ 2,816,577				$ 2,816,577				$ 2,569,348
Sales	371,926		357,397		727,706		715,127
Operating Income (Loss)	98,590		79,073		182,600		166,651
Depreciation, depletion and amortization	35,006		30,994		66,174		62,863
Forest Resources [Member]
Segment Reporting Information [Line Items]
Assets	1,627,553				1,627,553				1,603,515
Sales	52,663		57,037		104,858		105,217
Operating Income (Loss)	8,249		11,838		16,254		22,888
Depreciation, depletion and amortization	17,066		15,848		33,900		31,252
Real Estate Segment [Member]
Segment Reporting Information [Line Items]
Assets	112,555				112,555				102,682
Sales	11,680		12,305		24,326		25,767
Operating Income (Loss)	5,999		5,009		12,477		12,380
Depreciation, depletion and amortization	1,600		2,231		3,445		4,921
Performance Fibers Segment [Member]
Segment Reporting Information [Line Items]
Assets	769,780				769,780				646,447
Sales	254,509		232,807		505,364		483,970
Operating Income (Loss)	83,727		71,102		164,357		146,811
Depreciation, depletion and amortization	15,139		11,783		26,500		24,498
Wood Products Segment [Member]
Segment Reporting Information [Line Items]
Assets	21,294				21,294				21,264
Sales	23,830		17,957		43,039		33,747
Operating Income (Loss)	4,129		(987)		5,052		(534)
Depreciation, depletion and amortization	826		834		1,582		1,655
All Other Segments [Member]
Segment Reporting Information [Line Items]
Assets	21,735				21,735				24,576
Sales	29,268		38,508		50,409		68,920
Operating Income (Loss)	1,148		(965)		218		(166)
Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Sales	(24)	[1]	(1,217)	[1]	(290)	[1]	(2,494)	[1]
Unallocated Amount to Segment [Member]
Segment Reporting Information [Line Items]
Assets	263,660				263,660				170,864
Operating Income (Loss)	(4,662)		(6,924)		(15,758)		(14,728)
All Other Segments And Unallocated Amount To Segment [Member]
Segment Reporting Information [Line Items]
Depreciation, depletion and amortization	$ 375		$ 298		$ 747		$ 537

[1] Intersegment eliminations primarily reflect sales from our Forest Resources segment to our Performance Fibers segment