REVENUE (Disaggregation of Revenue by Product) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	$ 202,970	$ 194,198
Other Non-Timber Sales, Primarily Lease	226	293
Total Revenue	203,196	194,491
Pulpwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	35,126	30,333
Sawtimber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	122,576	101,175
Hardwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	597	716
Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	158,299	132,224
License Revenue, Primarily From Hunting
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	4,161	3,973
Other Non-Timber/Carbon Revenue
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	4,323	3,424
Agency Fee Income
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	123	288
Non-timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	8,607	7,685
Southern Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		38,935
Other Non-Timber Sales, Primarily Lease		203
Total Revenue	43,588	39,138
Southern Timber | Pulpwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		18,976
Southern Timber | Sawtimber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		13,023
Southern Timber | Hardwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		716
Southern Timber | Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		32,715
Southern Timber | License Revenue, Primarily From Hunting
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		3,830
Southern Timber | Other Non-Timber/Carbon Revenue
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		2,390
Southern Timber | Agency Fee Income
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		0
Southern Timber | Non-timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		6,220
Pacific Northwest Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		25,835
Other Non-Timber Sales, Primarily Lease		90
Total Revenue	31,374	25,925
Pacific Northwest Timber | Pulpwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		3,359
Pacific Northwest Timber | Sawtimber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		21,433
Pacific Northwest Timber | Hardwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		0
Pacific Northwest Timber | Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		24,792
Pacific Northwest Timber | License Revenue, Primarily From Hunting
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		97
Pacific Northwest Timber | Other Non-Timber/Carbon Revenue
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		946
Pacific Northwest Timber | Agency Fee Income
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		0
Pacific Northwest Timber | Non-timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		1,043
New Zealand Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		40,874
Other Non-Timber Sales, Primarily Lease		0
Total Revenue	52,964	40,874
New Zealand Timber | Pulpwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		5,161
New Zealand Timber | Sawtimber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		35,579
New Zealand Timber | Hardwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		0
New Zealand Timber | Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		40,740
New Zealand Timber | License Revenue, Primarily From Hunting
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		46
New Zealand Timber | Other Non-Timber/Carbon Revenue
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		88
New Zealand Timber | Agency Fee Income
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		0
New Zealand Timber | Non-timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		134
Real Estate
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	36,064	54,289
Other Non-Timber Sales, Primarily Lease		0
Total Revenue	36,064	54,289
Real Estate | Large Dispositions
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	41,951
Real Estate | Improved Development
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,121	0
Real Estate | Unimproved Development
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	7,446	0
Real Estate | Rural
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,652	6,739
Real Estate | Non-strategic / Timberlands
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	25,845	5,599
Trading
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		34,265
Other Non-Timber Sales, Primarily Lease		0
Total Revenue	39,212	34,265
Trading | Pulpwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		2,837
Trading | Sawtimber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		31,140
Trading | Hardwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		0
Trading | Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		33,977
Trading | License Revenue, Primarily From Hunting
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		0
Trading | Other Non-Timber/Carbon Revenue
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		0
Trading | Agency Fee Income
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		288
Trading | Non-timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		288
Operating Segments | Southern Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	43,419
Other Non-Timber Sales, Primarily Lease	169
Operating Segments | Southern Timber | Pulpwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	21,606
Operating Segments | Southern Timber | Sawtimber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	15,937
Operating Segments | Southern Timber | Hardwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	597
Operating Segments | Southern Timber | Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	38,140
Operating Segments | Southern Timber | License Revenue, Primarily From Hunting
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	4,084
Operating Segments | Southern Timber | Other Non-Timber/Carbon Revenue
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,195
Operating Segments | Southern Timber | Agency Fee Income
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0
Operating Segments | Southern Timber | Non-timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	5,279
Operating Segments | Pacific Northwest Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	31,317
Other Non-Timber Sales, Primarily Lease	57
Operating Segments | Pacific Northwest Timber | Pulpwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	3,419
Operating Segments | Pacific Northwest Timber | Sawtimber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	27,068
Operating Segments | Pacific Northwest Timber | Hardwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0
Operating Segments | Pacific Northwest Timber | Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	30,487
Operating Segments | Pacific Northwest Timber | License Revenue, Primarily From Hunting
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	25
Operating Segments | Pacific Northwest Timber | Other Non-Timber/Carbon Revenue
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	805
Operating Segments | Pacific Northwest Timber | Agency Fee Income
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0
Operating Segments | Pacific Northwest Timber | Non-timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	830
Operating Segments | New Zealand Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	52,964
Other Non-Timber Sales, Primarily Lease	0
Operating Segments | New Zealand Timber | Pulpwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	5,844
Operating Segments | New Zealand Timber | Sawtimber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	44,745
Operating Segments | New Zealand Timber | Hardwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0
Operating Segments | New Zealand Timber | Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	50,589
Operating Segments | New Zealand Timber | License Revenue, Primarily From Hunting
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	52
Operating Segments | New Zealand Timber | Other Non-Timber/Carbon Revenue
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	2,323
Operating Segments | New Zealand Timber | Agency Fee Income
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0
Operating Segments | New Zealand Timber | Non-timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	2,375
Operating Segments | Real Estate
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	36,064
Other Non-Timber Sales, Primarily Lease	0
Operating Segments | Real Estate | Large Dispositions
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0
Operating Segments | Real Estate | Improved Development
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,121
Operating Segments | Real Estate | Unimproved Development
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	7,446
Operating Segments | Real Estate | Rural
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,652
Operating Segments | Real Estate | Non-strategic / Timberlands
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	25,845
Operating Segments | Trading
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	39,206
Other Non-Timber Sales, Primarily Lease	0
Operating Segments | Trading | Pulpwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	4,257
Operating Segments | Trading | Sawtimber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	34,826
Operating Segments | Trading | Hardwood
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0
Operating Segments | Trading | Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	39,083
Operating Segments | Trading | License Revenue, Primarily From Hunting
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0
Operating Segments | Trading | Other Non-Timber/Carbon Revenue
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0
Operating Segments | Trading | Agency Fee Income
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	123
Operating Segments | Trading | Non-timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	123
Intersegment Eliminations
Disaggregation of Revenue [Line Items]
Total Revenue	(6)	$ 0
Intersegment Eliminations | Trading
Disaggregation of Revenue [Line Items]
Total Revenue	$ 6