REVENUE (Disaggregation of Revenue by Contract Type) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	$ 198,551	$ 156,417	$ 653,238	$ 532,764
Stumpage Pay-as-Cut
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	15,272	13,077	57,426	56,257
Stumpage Lump Sum
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	782	1,677	7,490	4,353
Total Stumpage
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	16,054	14,754	64,916	60,610
Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	143,675	120,785	365,785	383,405
Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	77,339	58,116	203,263	179,499
Total Delivered | Delivered Wood (Export)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	66,336	62,669	162,522	203,906
Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	159,729	135,539	430,701	444,015
Southern Timber | Stumpage Pay-as-Cut
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	14,518	13,077	56,141	56,257
Southern Timber | Stumpage Lump Sum
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	310	1,677	1,561	4,353
Southern Timber | Total Stumpage
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	14,828	14,754	57,702	60,610
Southern Timber | Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	27,349	18,258	73,513	60,427
Southern Timber | Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	21,976	16,597	64,473	52,977
Southern Timber | Total Delivered | Delivered Wood (Export)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	5,373	1,661	9,040	7,450
Pacific Northwest Timber | Stumpage Pay-as-Cut
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
Pacific Northwest Timber | Stumpage Lump Sum
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	472	0	5,929	0
Pacific Northwest Timber | Total Stumpage
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	472	0	5,929	0
Pacific Northwest Timber | Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	27,004	18,173	77,579	55,944
Pacific Northwest Timber | Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	27,004	18,173	77,579	55,944
Pacific Northwest Timber | Total Delivered | Delivered Wood (Export)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
New Zealand Timber | Stumpage Pay-as-Cut
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
New Zealand Timber | Stumpage Lump Sum
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
New Zealand Timber | Total Stumpage
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
New Zealand Timber | Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	59,343	59,345	135,702	174,983
New Zealand Timber | Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	20,127	22,722	45,944	65,161
New Zealand Timber | Total Delivered | Delivered Wood (Export)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	39,216	36,623	89,758	109,822
Timber Funds
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	8,633		15,279
Timber Funds | Stumpage Pay-as-Cut
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	754	0	1,285	0
Timber Funds | Stumpage Lump Sum
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
Timber Funds | Total Stumpage
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	754	0	1,285	0
Timber Funds | Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	7,870	0	13,971	0
Timber Funds | Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	7,870	0	13,971	0
Timber Funds | Total Delivered | Delivered Wood (Export)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
Trading
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	22,109	25,158	65,347	92,582
Trading | Stumpage Pay-as-Cut
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
Trading | Stumpage Lump Sum
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
Trading | Total Stumpage
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
Trading | Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	22,109	25,009	65,020	92,051
Trading | Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	362	624	1,296	5,417
Trading | Total Delivered | Delivered Wood (Export)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	21,747	24,385	63,724	86,634
Operating Segments | Southern Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	47,653	41,282	147,402	148,325
Operating Segments | Southern Timber | Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	42,177	33,012	131,215	121,037
Operating Segments | Pacific Northwest Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	28,885	18,766	86,131	57,856
Operating Segments | Pacific Northwest Timber | Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	27,476	18,173	83,508	55,944
Operating Segments | New Zealand Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	62,804	61,999	142,112	181,257
Operating Segments | New Zealand Timber | Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	59,343	59,345	135,702	174,983
Operating Segments | Timber Funds
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers		0		0
Operating Segments | Timber Funds | Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	8,624	0	15,256	0
Operating Segments | Trading | Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	$ 22,109	$ 25,009	$ 65,020	$ 92,051