v3.7.0.1
Income Taxes (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Income Tax Contingency [Line Items]    
Effective income tax rate reconciliation, distribution of earnings from foreign partnership (percent)   19.00%
Income tax expense $ 24 $ 51
Effective tax rate (percent) 12.40% 35.80%