v3.8.0.1
Income Taxes - Tax Effects Of Temporary Differences Which Give Rise To Deferred Tax Assets And Liabilities (Details) - USD ($)
$ in Millions
Dec. 31, 2017
Dec. 31, 2016
Income Tax Disclosure [Abstract]    
Medical claims liability $ 46 $ 66
Nondeductible liabilities 41 39
Net operating loss and tax credit carryforwards 94 101
Compensation accruals 129 156
Premium and trade receivables 45 79
Other 11 14
Deferred tax assets 366 455
Valuation allowance (81) (86)
Net deferred tax assets 285 369
Intangible assets 342 577
Prepaid assets 23 17
Fixed assets 84 65
Investments in joint ventures 20 11
Deferred revenue 26 0
Other 17 2
Deferred tax liabilities 512 672
Deferred tax liabilities, net $ (227) $ (303)