XML 80 R64.htm IDEA: XBRL DOCUMENT v3.10.0.1
Summary of Significant Accounting Policies - Net Income/(Loss) Attributable to Continuing and Discontinued Operations (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Accounting Policies [Abstract]      
Income/(loss) from continuing operations, net of income tax $ 465 $ (977) $ (733)
Loss from discontinued operations, net of income tax (197) (1,176) (41)
Net Income/(Loss) Attributable to NRG Energy, Inc. $ 268 $ (2,153) $ (774)