Segment Information (Summary of Revenues by Major Product) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Disaggregation Of Revenue [Line Items]
Revenues		$ 354,193	$ 208,880
Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenues		401,525	238,394
Intersegment Eliminations [Member]
Disaggregation Of Revenue [Line Items]
Revenues	[1]	(47,332)	(29,514)
Timberlands [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenues		111,916	82,425
Timberlands [Member] | Operating Segments [Member] | Northern Region [Member]
Disaggregation Of Revenue [Line Items]
Revenues		76,980	43,461
Timberlands [Member] | Operating Segments [Member] | Northern Region [Member] | Sawlogs [Member]
Disaggregation Of Revenue [Line Items]
Revenues		76,181	41,407
Timberlands [Member] | Operating Segments [Member] | Northern Region [Member] | Pulpwood [Member]
Disaggregation Of Revenue [Line Items]
Revenues		499	1,435
Timberlands [Member] | Operating Segments [Member] | Northern Region [Member] | Stumpage [Member]
Disaggregation Of Revenue [Line Items]
Revenues			316
Timberlands [Member] | Operating Segments [Member] | Northern Region [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Revenues		300	303
Timberlands [Member] | Operating Segments [Member] | Southern Region [Member]
Disaggregation Of Revenue [Line Items]
Revenues		34,936	38,964
Timberlands [Member] | Operating Segments [Member] | Southern Region [Member] | Sawlogs [Member]
Disaggregation Of Revenue [Line Items]
Revenues		22,416	23,939
Timberlands [Member] | Operating Segments [Member] | Southern Region [Member] | Pulpwood [Member]
Disaggregation Of Revenue [Line Items]
Revenues		9,161	11,201
Timberlands [Member] | Operating Segments [Member] | Southern Region [Member] | Stumpage [Member]
Disaggregation Of Revenue [Line Items]
Revenues		764	829
Timberlands [Member] | Operating Segments [Member] | Southern Region [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Revenues		2,595	2,995
Wood Products [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenues		269,296	145,000
Wood Products [Member] | Operating Segments [Member] | Lumber [Member]
Disaggregation Of Revenue [Line Items]
Revenues		229,682	111,939
Wood Products [Member] | Operating Segments [Member] | Residuals and Panels [Member]
Disaggregation Of Revenue [Line Items]
Revenues		39,614	33,061
Real Estate Segment [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenues		20,313	10,969
Real Estate Segment [Member] | Operating Segments [Member] | Rural Real Estate [Member]
Disaggregation Of Revenue [Line Items]
Revenues		10,025	7,292
Real Estate Segment [Member] | Operating Segments [Member] | Development Real Estate [Member]
Disaggregation Of Revenue [Line Items]
Revenues		8,053	2,292
Real Estate Segment [Member] | Operating Segments [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Revenues		$ 2,235	$ 1,385

[1] Intersegment revenues represent logs sold by our Timberlands segment to our Wood Products segment.