Segment and Geographic Area Information - Geographic Information Table (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Geographical Information [Line Items]
Revenues from external customers	$ 8,599	$ 8,209	$ 8,420
Long-lived assets	1,469	1,356	1,351
Total assets	4,342	3,967	3,996
United States
Schedule Of Geographical Information [Line Items]
Revenues from external customers	3,512	3,362	3,348
Long-lived assets	541	496	473
Total assets	1,897	1,726	1,696
China
Schedule Of Geographical Information [Line Items]
Revenues from external customers	1,186	1,101	1,079
Long-lived assets	217	203	192
Total assets	791	696	683
Germany
Schedule Of Geographical Information [Line Items]
Revenues from external customers	764	807	955
Long-lived assets	111	108	113
Total assets	231	258	319
Canada
Schedule Of Geographical Information [Line Items]
Revenues from external customers	387	387	413
Long-lived assets	44	41	52
Total assets	166	146	164
United Kingdom
Schedule Of Geographical Information [Line Items]
Revenues from external customers	387	307	235
Long-lived assets	38	32	27
Total assets	130	101	68
Other Foreign
Schedule Of Geographical Information [Line Items]
Revenues from external customers	2,363	2,245	2,390
Long-lived assets	518	476	494
Total assets	1,275	1,156	1,221
Reclass & Elims
Schedule Of Geographical Information [Line Items]
Revenues from external customers	0	0	0
Long-lived assets	0	0	0
Total assets	$ (148)	$ (116)	$ (155)