Goodwill and Other Intangible Assets - Estimated Aggregate Pre-Tax Amortization Expense Related to Intangible Assets (Details) $ in Millions	Mar. 31, 2016 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense remainder of 2016	$ 7
Amortization expense 2017	6
Amortization expense 2018	3
Amortization expense 2019	2
Amortization expense 2020	$ 1