MERGER WITH PLUM CREEK Additional Information (Details) - Plum Creek - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Total assets acquired	$ 10,000
Estimated consideration transferred	6,400
Total liabilities assumed	3,600
Non-recurring merger-related costs	$ 155	$ 22