Income Taxes - Tax Attributable Carryforwards (Details) $ in Millions	Dec. 31, 2015 USD ($)
Domestic
Tax Credit Carryforward [Line Items]
Net operating losses - regular income tax	$ 0
Net operating losses – state income tax	32
Foreign tax credits	26
Foreign
Tax Credit Carryforward [Line Items]
Net operating losses - regular income tax	316
Net operating losses – state income tax	0
Foreign tax credits	$ 0