Equity (Details of Stock Options) (Details) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2016 USD ($) $ / shares shares
Equity [Abstract]
Number of Options, Vested or expected to vest | shares	832,221
Weighted Average Exercise Price, Vested or expected to vest | $ / shares	$ 177.80
Weighted Average Remaining Contractual Life, Vested or expected to vest	6 years 10 months 24 days
Aggregate Intrinsic Value, Vested or expected to vest | $	$ 65
Number of Options, Exercised | shares	559,552
Weighted Average Exercise Price, Exercised | $ / shares	$ 151.84
Weighted Average Remaining Contractual Life, Exercised	5 years 10 months 24 days
Aggregate Intrinsic Value, Exercised | $	$ 58