REVENUE - Disaggregation of Revenue by Contract Type (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	$ 858,549	$ 711,556	$ 816,138
Southern Timber | Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	191,831	194,111	169,995
Pacific Northwest Timber | Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	120,809	85,414	109,832
New Zealand Timber | Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	202,315	241,861	249,014
Timber Funds | Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	26,120
Trading | Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	88,734	115,283	148,722
Total Timber Sales
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	594,899	587,895	640,347
Total Timber Sales | Southern Timber | Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	170,221	159,156	143,863
Total Timber Sales | Pacific Northwest Timber | Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	116,632	82,727	106,471
Total Timber Sales | New Zealand Timber | Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	194,493	231,406	241,943
Total Timber Sales | Timber Funds | Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	25,979	0	0
Total Timber Sales | Trading
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers			148,070
Total Timber Sales | Trading | Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	87,574	114,606	148,070
Total Timber Sales | Stumpage Pay-as-Cut
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	70,415	71,943	72,385
Total Timber Sales | Stumpage Pay-as-Cut | Southern Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	68,684	71,943	72,385
Total Timber Sales | Stumpage Pay-as-Cut | Pacific Northwest Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0
Total Timber Sales | Stumpage Pay-as-Cut | Timber Funds
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,731	0	0
Total Timber Sales | Stumpage Lump Sum
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	10,169	10,177	16,842
Total Timber Sales | Stumpage Lump Sum | Southern Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	2,027	7,428	4,988
Total Timber Sales | Stumpage Lump Sum | Pacific Northwest Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	8,142	2,749	11,854
Total Timber Sales | Stumpage Lump Sum | Timber Funds
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0
Total Timber Sales | Total Stumpage
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	80,584	82,120	89,227
Total Timber Sales | Total Stumpage | Southern Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	70,711	79,371	77,373
Total Timber Sales | Total Stumpage | Pacific Northwest Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	8,142	2,749	11,854
Total Timber Sales | Total Stumpage | Timber Funds
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,731	0	0
Total Timber Sales | Total Delivered
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	514,315	505,775	551,120
Total Timber Sales | Total Delivered | Southern Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	99,510	79,785	66,490
Total Timber Sales | Total Delivered | Pacific Northwest Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	108,490	79,978	94,617
Total Timber Sales | Total Delivered | New Zealand Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	194,493	231,406	241,943
Total Timber Sales | Total Delivered | Timber Funds
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	24,248	0	0
Total Timber Sales | Total Delivered | Trading
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	87,574	114,606
Total Timber Sales | Total Delivered | Domestic
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	283,070	237,494	252,320
Total Timber Sales | Total Delivered | Domestic | Southern Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	85,996	71,054	60,931
Total Timber Sales | Total Delivered | Domestic | Pacific Northwest Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	108,490	79,978	94,617
Total Timber Sales | Total Delivered | Domestic | New Zealand Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	62,568	80,974	90,631
Total Timber Sales | Total Delivered | Domestic | Timber Funds
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	24,248	0	0
Total Timber Sales | Total Delivered | Domestic | Trading
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,768	5,488	6,141
Total Timber Sales | Total Delivered | Export
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	231,245	268,281	298,800
Total Timber Sales | Total Delivered | Export | Southern Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	13,514	8,731	5,559
Total Timber Sales | Total Delivered | Export | Pacific Northwest Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0
Total Timber Sales | Total Delivered | Export | New Zealand Timber
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	131,925	150,432	151,312
Total Timber Sales | Total Delivered | Export | Timber Funds
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0
Total Timber Sales | Total Delivered | Export | Trading
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	$ 85,806	$ 109,118	$ 141,929