BUSINESS SEGMENTS - Total Assets (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 18,059	$ 19,243	$ 12,720
Operating segments | Timberlands and Real Estate & ENR
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	14,122	15,608	7,260
Operating segments | Wood Products
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	2,145	1,910	1,541
Unallocated Items
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 1,792	$ 1,725	$ 3,919