Fair Value of Financial Assets and Liabilities - Recurring (Details) - Fair Value, Measurements, Recurring [Member] - Significant Other Observable Inputs (Level 2) [Member] - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Assets:
Interest rate swaps	$ 15	$ 7
Deferred compensation investments in cash surrender life insurance	97	92
Deferred compensation investments in mutual funds	35	33
Total	233	187
Liabilities:
Deferred compensation plan liabilities	127	125
Total	135	138
Foreign Exchange Forward [Member]
Assets:
Foreign exchange contracts	86	55
Liabilities:
Foreign derivative contracts	8	12
Currency options [Member]
Liabilities:
Foreign derivative contracts	$ 0	$ 1