DEBT - Narrative and Debt Covenants (Details) $ in Millions	1 Months Ended		3 Months Ended		5 Months Ended	6 Months Ended
	Jun. 30, 2021 USD ($)	May 31, 2021 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	May 31, 2021	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 NZD ($)
Debt Instrument [Line Items]
Debt issuance costs						$ 4,812,000	$ 2,427,000
Repayments of debt						350,000,000	117,000,000
Interest and other miscellaneous (expense) income, net			$ (1,144,000)	$ 1,579,000		(1,148,000)	$ 1,370,000
Repayments						0
Excluding Timber Funds
Debt Instrument [Line Items]
Capitalized financing costs	$ 5,348,000		5,348,000			5,348,000
Total long-term debt	$ 1,394,171,000		$ 1,394,171,000			$ 1,394,171,000
Excluding Timber Funds | Senior Notes Due 2031
Debt Instrument [Line Items]
Amount issued and sold		$ 450,000,000
Stated interest rate	2.75%	2.75%	2.75%		2.75%	2.75%		2.75%
Issue price, percent		99.195%
Debt issuance costs		$ 3,900,000
Proceeds from debt		$ 442,500,000
Total long-term debt	$ 450,000,000		$ 450,000,000			$ 450,000,000
Excluding Timber Funds | Senior Notes due 2022
Debt Instrument [Line Items]
Stated interest rate	3.75%	3.75%	3.75%		3.75%	3.75%		3.75%
Total long-term debt	$ 325,000,000		$ 325,000,000			$ 325,000,000
Excluding Timber Funds | Working Capital Facility
Debt Instrument [Line Items]
Repayments						0
Borrowings						0
Remaining borrowing capacity								$ 20.0
Term of extension	12 months
Excluding Timber Funds | Minority Shareholder Due 2025 At 2.95% | Matariki Forestry Group
Debt Instrument [Line Items]
Outstanding balance	$ 24,200,000		$ 24,200,000			$ 24,200,000
Excluding Timber Funds | Term Credit Agreement
Debt Instrument [Line Items]
Stated interest rate	1.70%		1.70%			1.70%		1.70%
Maximum borrowing capacity	$ 350,000,000		$ 350,000,000			$ 350,000,000
Total long-term debt	$ 350,000,000		$ 350,000,000			$ 350,000,000
Excluding Timber Funds | Term Credit Agreement | LIBOR
Debt Instrument [Line Items]
Basis points on periodic interest rate						1.60%
Excluding Timber Funds | Incremental Term Loan Agreement
Debt Instrument [Line Items]
Stated interest rate	1.70%		1.70%			1.70%		1.70%
Maximum borrowing capacity	$ 200,000,000		$ 200,000,000			$ 200,000,000
Total long-term debt	200,000,000		200,000,000			$ 200,000,000
Excluding Timber Funds | Incremental Term Loan Agreement | LIBOR
Debt Instrument [Line Items]
Basis points on periodic interest rate						1.65%
Excluding Timber Funds | 2020 Incremental Term Loan Agreement
Debt Instrument [Line Items]
Repayments of debt		$ 250,000,000
Gain (loss) on extinguishment of debt		$ 600,000
Maximum borrowing capacity	200,000,000		200,000,000			$ 200,000,000
Excluding Timber Funds | 2026 Incremental Term Loan
Debt Instrument [Line Items]
Repayments of debt						100,000,000
Gain (loss) on extinguishment of debt						(100,000)
Total long-term debt	300,000,000		300,000,000			300,000,000
Timber Funds
Debt Instrument [Line Items]
Capitalized financing costs	7,000		7,000			7,000
Total long-term debt	$ 57,380,000		$ 57,380,000			$ 57,380,000
Timber Funds | Fund II Mortgages Payable
Debt Instrument [Line Items]
Loan-to-value ratio, percentage						50.00%
Timber Funds | Fund III Mortgages Payable
Debt Instrument [Line Items]
Loan-to-value ratio, percentage						50.00%
Ratio of minimum interest coverage	1.5		1.5			1.5		1.5
Working capital						$ 500,000
Timber Funds | Fund II Mortgages Payable, Due 2022 At 1.700% | LIBOR
Debt Instrument [Line Items]
Basis points on periodic interest rate						1.70%
2021 Incremental Term Loan Facility | Excluding Timber Funds
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 200,000,000		$ 200,000,000			$ 200,000,000
Capitalized financing costs	200,000		200,000			200,000
Advance amount	200,000,000		200,000,000			200,000,000
Amount outstanding	0		0			0
Amount of future advance expected	125,000,000		125,000,000			125,000,000
Deferred commitment fees	$ 300,000		$ 300,000			$ 300,000
2021 Incremental Term Loan Facility | Excluding Timber Funds | Senior Notes due 2022
Debt Instrument [Line Items]
Stated interest rate	3.75%		3.75%			3.75%		3.75%
Revolving Credit Facility
Debt Instrument [Line Items]
Borrowings						$ 0
Revolving Credit Facility | Excluding Timber Funds
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 300,000,000		$ 300,000,000			300,000,000
Capitalized financing costs	300,000		300,000			300,000
Remaining borrowing capacity	299,100,000		299,100,000			299,100,000
Amount to secure outstanding letters of credit	$ 900,000		900,000			900,000
Revolving Credit Facility | Excluding Timber Funds | LIBOR
Debt Instrument [Line Items]
Basis points on periodic interest rate	1.25%				1.50%
Northwest Farm Credit Services Credit Facility | Excluding Timber Funds
Debt Instrument [Line Items]
Capitalized financing costs	$ 100,000		100,000			100,000
Total long-term debt	45,000,000		45,000,000			45,000,000
Long-term debt fair value	45,000,000		45,000,000			45,000,000
2016 Incremental Term Loan Facility | Excluding Timber Funds
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 300,000,000		$ 300,000,000			300,000,000
Interest and other miscellaneous (expense) income, net						$ (300,000)
2016 Incremental Term Loan Facility | Excluding Timber Funds | LIBOR
Debt Instrument [Line Items]
Basis points on periodic interest rate	1.65%				1.90%