Segment Information (Reconciliation of Business Segment Total Assets to Total Assets) (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Segment Reporting Asset Reconciling Item [Line Items]
Assets		$ 2,413,071	$ 953,079
Operating Segments [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Assets		2,277,515	824,719
Operating Segments [Member] | Resource [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Assets	[1]	1,719,703	670,240
Operating Segments [Member] | Wood Products [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Assets		468,622	154,479
Operating Segments [Member] | Real Estate [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Assets	[2]	89,190
Corporate [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Assets		$ 135,556	$ 128,360

[1] We do not report rural real estate separate from Resource as we do not report these assets separately to management.

[2] Real Estate assets primarily consist of real estate development acquired with the Deltic merger.