Intangible Assets - Intangible Assets with Definite Lives (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Intangible Assets with Definite Lives:
Gross Carrying Amount	$ 79	$ 79
Accumulated Amortization	(69)	(61)
Net	10	18
Customer relationships
Intangible Assets with Definite Lives:
Gross Carrying Amount	70	70
Accumulated Amortization	(61)	(54)
Net	9	16
Other
Intangible Assets with Definite Lives:
Gross Carrying Amount	9	9
Accumulated Amortization	(8)	(7)
Net	$ 1	$ 2