CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accumulated deficit	$ (1,013)		$ (1,009)
ASU 2016-16
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect		$ 1
ASU 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accumulated deficit		(1,008)
Adjustment | ASU 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accumulated deficit		$ 1