Segment Information (Summary of Revenues by Major Product) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation Of Revenue [Line Items]
Revenues		$ 447,506	$ 181,555	$ 801,699	$ 390,435
Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenues		494,887	206,666	896,412	445,060
Intersegment Eliminations [Member]
Disaggregation Of Revenue [Line Items]
Revenues	[1]	(47,381)	(25,111)	(94,713)	(54,625)
Timberlands [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenues		121,216	67,345	233,132	149,770
Timberlands [Member] | Operating Segments [Member] | Northern Region [Member]
Disaggregation Of Revenue [Line Items]
Revenues		87,205	32,166	164,185	75,627
Timberlands [Member] | Operating Segments [Member] | Northern Region [Member] | Sawlogs [Member]
Disaggregation Of Revenue [Line Items]
Revenues		86,773	30,638	162,954	72,045
Timberlands [Member] | Operating Segments [Member] | Northern Region [Member] | Pulpwood [Member]
Disaggregation Of Revenue [Line Items]
Revenues		197	1,236	696	2,671
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		235	292	535	595
Timberlands [Member] | Operating Segments [Member] | Southern Region [Member]
Disaggregation Of Revenue [Line Items]
Revenues		34,011	35,179	68,947	74,143
Timberlands [Member] | Operating Segments [Member] | Southern Region [Member] | Sawlogs [Member]
Disaggregation Of Revenue [Line Items]
Revenues		21,013	21,205	43,429	45,144
Timberlands [Member] | Operating Segments [Member] | Southern Region [Member] | Pulpwood [Member]
Disaggregation Of Revenue [Line Items]
Revenues		10,163	10,872	19,324	22,073
Timberlands [Member] | Operating Segments [Member] | Southern Region [Member] | Stumpage [Member]
Disaggregation Of Revenue [Line Items]
Revenues		271	817	1,035	1,646
Timberlands [Member] | Operating Segments [Member] | Southern Region [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Revenues		2,564	2,285	5,159	5,280
Wood Products [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenues		357,673	126,216	626,969	271,216
Wood Products [Member] | Operating Segments [Member] | Lumber [Member]
Disaggregation Of Revenue [Line Items]
Revenues		308,480	102,793	538,162	214,732
Wood Products [Member] | Operating Segments [Member] | Residuals and Panels [Member]
Disaggregation Of Revenue [Line Items]
Revenues		49,193	23,423	88,807	56,484
Real Estate Segment [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenues		15,998	13,105	36,311	24,074
Real Estate Segment [Member] | Operating Segments [Member] | Rural Real Estate [Member]
Disaggregation Of Revenue [Line Items]
Revenues		11,505	9,879	21,530	17,171
Real Estate Segment [Member] | Operating Segments [Member] | Development Real Estate [Member]
Disaggregation Of Revenue [Line Items]
Revenues		1,774	1,672	9,827	3,964
Real Estate Segment [Member] | Operating Segments [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Revenues		$ 2,719	$ 1,554	$ 4,954	$ 2,939

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