Taxes on Income (Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	$ 93	$ 48
Additions for tax positions related to the current year	22	16
Additions for tax positions related to prior years	15	32
Reductions for tax positions related to prior years	(2)	(2)
Reductions due to lapse of statute of limitations	0	0
Reductions for settlements with tax authorities	(17)	(1)
Balance at end of year	$ 111	$ 93