DEBT (Narrative and Debt Convenants) (Details) $ in Millions		6 Months Ended
	May 08, 2020 USD ($) mortgage_payable	Jun. 30, 2020 USD ($) tranche	Jun. 30, 2020 NZD ($)	Apr. 16, 2020 USD ($)	Apr. 13, 2020 USD ($)	Apr. 12, 2020 USD ($)	Apr. 01, 2020 USD ($)	Mar. 31, 2020 USD ($)
Debt Instrument [Line Items]
Debt instrument, number of tranches | tranche		5
Excluding Timber Funds
Debt Instrument [Line Items]
Total debt, excluding Timber Funds		$ 1,313,355,000
Timber Funds
Debt Instrument [Line Items]
Total debt, excluding Timber Funds		60,659,000
Fund II Mortgages Payable
Debt Instrument [Line Items]
Face amount	$ 25,000,000.0	$ 25,000,000
Debt instrument, number of mortgages payable | mortgage_payable	2
Fund II Mortgages Payable | Timber Funds
Debt Instrument [Line Items]
Loan-to-value ratio, percentage		50.00%
Fund III Mortgages Payable
Debt Instrument [Line Items]
Face amount	$ 32,400,000	$ 32,380,000
Debt instrument, number of mortgages payable | mortgage_payable	2
Fund III Mortgages Payable | Timber Funds
Debt Instrument [Line Items]
Loan-to-value ratio, percentage		50.00%
Ratio of minimum interest coverage		1.5	1.5
Working capital		$ 500,000
2020 Incremental Term Loan Facility
Debt Instrument [Line Items]
Debt term				5 years
Face amount				$ 250,000,000
2020 Incremental Term Loan Facility | Excluding Timber Funds
Debt Instrument [Line Items]
Total debt, excluding Timber Funds		250,000,000
Working Capital Facility
Debt Instrument [Line Items]
Proceeds from lines of credit		0
Repayments of lines of credit		0
Remaining borrowing capacity			$ 20.0
Term Credit Agreement | Excluding Timber Funds
Debt Instrument [Line Items]
Total debt, excluding Timber Funds		$ 350,000,000
Covenant EBITDA to consolidated interest expense, Covenant Requirement		2.5	2.5
Covenant EBITDA to consolidated interest expense, Actual ratio		9.8	9.8
Covenant EBITDA to consolidated interest expense, Favorable		7.3	7.3
Covenant debt to net worth plus covenant debt, Covenant Requirement		0.65	0.65
Covenant debt to net worth plus covenant debt, Actual ratio		0.47	0.47
Covenant debt to net worth plus covenant debt, favorable		0.18	0.18
Incremental Term Loan Agreement borrowings due 2026 | Excluding Timber Funds
Debt Instrument [Line Items]
Total debt, excluding Timber Funds		$ 300,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 300,000,000	$ 250,000,000	$ 250,000,000	$ 200,000,000
Proceeds from lines of credit		70,000,000.0
Repayments of lines of credit		117,000,000.0
Remaining borrowing capacity		264,000,000.0
Amount to secure outstanding letters of credit		1,000,000.0
Revolving Credit Facility | Excluding Timber Funds
Debt Instrument [Line Items]
Maximum borrowing capacity		300,000,000
Northwest Farm Credit Services Credit Facility
Debt Instrument [Line Items]
Face amount	$ 45,000,000.0	45,000,000
Northwest Farm Credit Services Credit Facility | Excluding Timber Funds
Debt Instrument [Line Items]
Long-term debt fair value		$ 45,000,000
Covenant EBITDA to consolidated interest expense, Covenant Requirement		2.5	2.5
Covenant EBITDA to consolidated interest expense, Actual ratio		9.8	9.8
Covenant EBITDA to consolidated interest expense, Favorable		7.3	7.3
Covenant debt to net worth plus covenant debt, Covenant Requirement		0.65	0.65
Covenant debt to net worth plus covenant debt, Actual ratio		0.47	0.47
Covenant debt to net worth plus covenant debt, favorable		0.18	0.18
Ratio of loan To appraised value, Covenant Requirement		50	50
Ratio of loan to appraised value requirement actual		11	11
Ratio of loan to appraised value, favorable		0.39	0.39