XML 66 R53.htm IDEA: XBRL DOCUMENT v3.22.2.2
Significant Accounting Policies (Reconciliation of Total Cash, Restricted Cash and Equivalents) (Parenthetical) (Detail) - USD ($)
$ in Millions
Sep. 30, 2022
Dec. 31, 2021
Sep. 30, 2021
Dec. 31, 2020
Cash Cash Equivalents And Restricted Cash [Line Items]        
Cash and cash equivalents $ 163 $ 283 [1]    
Restricted cash and equivalents $ 0 $ 0 $ 22 $ 3
Restricted Cash Equivalents, Current, Statement of Financial Position [Extensible Enumeration] Current assets held for sale Current assets held for sale Current assets held for sale Current assets held for sale
Current Assets Held for Sale        
Cash Cash Equivalents And Restricted Cash [Line Items]        
Cash and cash equivalents $ 0 $ 0 $ 15 $ 7
[1] Dominion Energy’s Consolidated Balance Sheet at December 31, 2021 has been derived from the audited Consolidated Balance Sheet at that date.