XML 120 R97.htm IDEA: XBRL DOCUMENT v3.20.4
Income Taxes - Components (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Current income tax expense:      
State income tax $ 0 $ 3 $ 3
Canadian federal and provincial income tax 51 109 63
Total current income tax expense 51 112 66
Deferred income tax expense/(benefit):      
Federal income tax (149) 89 90
State income tax 1 21 14
Canadian federal and provincial income tax (70) (46) 132
Total deferred income tax expense/(benefit) (218) 64 236
Total income tax expense/(benefit) $ (167) $ 176 $ 302