Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES
Net income		$ 163,880	$ 131,106
Adjustments to reconcile net income to net cash from operating activities:
Depreciation, depletion and amortization		19,874	18,399
Basis of real estate sold		10,854	8,823
Change in deferred taxes		(2,123)	1,490
Pension and other postretirement employee benefits		3,857	5,627
Pension settlement charge		14,165
Equity-based compensation expense		2,056	1,930
Net loss on fire damage		276
Other, net		(291)	(387)
Change in working capital and operating-related activities, net		21,208	6,713
Real estate development expenditures		(2,161)	(2,315)
Funding of pension and other postretirement employee benefits		(1,296)	(1,421)
Net cash from operating activities		230,299	169,965
CASH FLOWS FROM INVESTING ACTIVITIES
Property, plant and equipment additions		(12,566)	(7,762)
Timberlands reforestation and roads		(4,648)	(3,956)
Other, net		92	189
Net cash from investing activities		(17,122)	(11,529)
CASH FLOWS FROM FINANCING ACTIVITIES
Distributions to common stockholders		(30,524)	(27,484)
Repayments of long term debt		(3,000)
Other, net		(1,071)	(591)
Net cash from financing activities		(34,595)	(28,075)
Change in cash, cash equivalents and restricted cash		178,582	130,361
Cash, cash equivalents and restricted cash at beginning of period		296,772	252,340
Cash, cash equivalents and restricted cash at end of period		475,354	382,701
NONCASH INVESTING AND FINANCING ACTIVITIES
Accrued property, plant and equipment additions		1,516	2,263
Accrued timberlands reforestation and roads		98	813
Cash and cash equivalents		470,918	382,032
Restricted cash included in other long-term assets	[1]	$ 4,436	$ 669
Restricted Cash, Asset, Statement of Financial Position [Extensible List]		us-gaap:OtherAssetsMember	us-gaap:OtherAssetsMember
Total cash, cash equivalents, and restricted cash		$ 475,354	$ 382,701

[1] Amounts included in restricted cash represent proceeds held by a qualified intermediary that are intended to be reinvested in timber and timberlands.