XML 331 R283.htm IDEA: XBRL DOCUMENT v3.22.0.1
Fair Value Measurements - Level 3 (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Commodity Derivatives      
Fair Value, Assets (Liabilities), Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]      
Beginning balance $ 116 $ 97 $ 99
Changes included in earnings (43) (10) 10
Changes in fair value recognized in OCI (13) 0 (1)
Changes in fair value recognized in net regulatory assets (118) (17) (26)
Purchases (76) 5 6
Settlements (34) 41 9
Transfers to Level 2 17 0 0
Ending balance (151) 116 97
Interest Rate Derivatives      
Fair Value, Assets (Liabilities), Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]      
Beginning balance 62 14 10
Changes included in earnings (43) 48 4
Changes in fair value recognized in OCI 0 0 0
Changes in fair value recognized in net regulatory assets 0 0 0
Purchases 0 0 0
Settlements 0 0 0
Transfers to Level 2 0 0 0
Ending balance $ 19 $ 62 $ 14