REVENUE (Disaggregation of Revenue by Contract Type) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	$ 195,558	$ 184,800	$ 454,688	$ 376,346
Stumpage Pay-as-Cut
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	16,747	15,172	42,154	43,180
Stumpage Lump Sum
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,189	581	6,708	2,675
Total Stumpage
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	17,936	15,753	48,862	45,855
Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	120,705	135,119	222,111	262,620
Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	65,261	59,123	125,925	121,382
Total Delivered | Delivered Wood (Export)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	55,444	75,996	96,186	141,238
Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	138,641	150,872	270,973	308,475
Southern Timber | Stumpage Pay-as-Cut
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	16,216	15,172	41,623	43,180
Southern Timber | Stumpage Lump Sum
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	863	581	1,251	2,675
Southern Timber | Total Stumpage
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	17,079	15,753	42,874	45,855
Southern Timber | Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	24,477	21,234	46,165	42,168
Southern Timber | Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	21,438	17,041	42,498	36,379
Southern Timber | Total Delivered | Delivered Wood (Export)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	3,039	4,193	3,667	5,789
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	326	0	5,457	0
Pacific Northwest Timber | Total Stumpage
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	326	0	5,457	0
Pacific Northwest Timber | Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	25,133	17,674	50,574	37,771
Pacific Northwest Timber | Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	25,133	17,674	50,574	37,771
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	40,725	61,008	76,359	115,639
New Zealand Timber | Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	12,126	21,739	25,817	42,439
New Zealand Timber | Total Delivered | Delivered Wood (Export)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	28,599	39,269	50,542	73,200
Timber Funds
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	6,647		6,647
Timber Funds | Stumpage Pay-as-Cut
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	531	0	531	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	531	0	531	0
Timber Funds | Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	6,102	0	6,102	0
Timber Funds | Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	6,102	0	6,102	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	24,267	35,387	43,238	67,423
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	24,268	35,203	42,911	67,042
Trading | Total Delivered | Delivered Wood (Domestic)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	462	2,669	934	4,793
Trading | Total Delivered | Delivered Wood (Export)
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	23,806	32,534	41,977	62,249
Operating Segments | Southern Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	46,767	46,197	99,749	107,043
Operating Segments | Southern Timber | Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	41,556	36,987	89,039	88,023
Operating Segments | Pacific Northwest Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	26,171	18,556	57,245	39,091
Operating Segments | Pacific Northwest Timber | Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	25,459	17,674	56,031	37,771
Operating Segments | New Zealand Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	41,769	62,127	79,308	119,257
Operating Segments | New Zealand Timber | Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	40,725	61,008	76,359	115,639
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	6,633	0	6,633	0
Operating Segments | Trading | Total Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	$ 24,268	$ 35,203	$ 42,911	$ 67,042