CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Cash Flows [Abstract]
Interest paid (net of capitalized interest of $53, $78 and $54)	$ 53	$ 78	$ 54
Cash acquired for Level 3 acquisition		$ 2,300