CONSOLIDATED STATEMENT OF CASH FLOWS (UNAUDITED) (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Statement of Cash Flows [Abstract]
Cash at beginning/end of period, discontinued operations	$ 6	$ 7	$ 10	$ 12