Goodwill (details) - Other Intangible Assets - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Goodwill and Other Intangible Assets disclosure
Intangible assets subject to amortization, gross carrying amount	$ 209		$ 210
Intangible assets subject to amortization, accumulated amortization	151		148
Intangible assets subject to amortization, net	58		62
Intangible assets not subject to amortization	217		217
Total other intangible assets, gross carrying amount	426		427
Total other intangible assets, net	275		$ 279
Amortization expense of intangible assets	3	$ 11
Estimated intangible asset amortization expense, remainder of 2016	8
Estimated intangible asset amortization expense, 2017	9
Estimated intangible asset amortization expense, 2018	8
Estimated intangible asset amortization expense, 2019	6
Estimated intangible asset amortization expense, 2020	$ 5