Regulatory Assets and Liabilities (Schedule of Regulatory Liabilities) (Details) - USD ($) $ in Millions		Sep. 30, 2017	Dec. 31, 2016
Regulatory Liabilities [Line Items]
Regulatory liabilities-current		$ 88	$ 163	[1]
Regulatory liabilities-noncurrent		2,906	2,622	[1]
Total regulatory liabilities		2,994	2,785
Deferred cost of fuel used in electric generation
Regulatory Liabilities [Line Items]
Regulatory liabilities-current	[2]	5	61
PIPP
Regulatory Liabilities [Line Items]
Regulatory liabilities-current	[3]	20	28
Other
Regulatory Liabilities [Line Items]
Regulatory liabilities-current		63	74
Regulatory liabilities-noncurrent		211	119
Provision for future cost of removal and AROs
Regulatory Liabilities [Line Items]
Regulatory liabilities-noncurrent	[4]	1,477	1,427
Nuclear decommissioning trust
Regulatory Liabilities [Line Items]
Regulatory liabilities-noncurrent	[5]	1,034	902
Derivatives
Regulatory Liabilities [Line Items]
Regulatory liabilities-noncurrent	[6]	78	69
Pension and Other Postretirement Plans Costs
Regulatory Liabilities [Line Items]
Regulatory liabilities-noncurrent		106	105
Virginia Electric and Power Company
Regulatory Liabilities [Line Items]
Regulatory liabilities-current	[7]	43	115
Regulatory liabilities-noncurrent		2,202	1,962	[8]
Total regulatory liabilities		2,245	2,077
Virginia Electric and Power Company | Deferred cost of fuel used in electric generation
Regulatory Liabilities [Line Items]
Regulatory liabilities-current	[2]	5	61
Virginia Electric and Power Company | Other
Regulatory Liabilities [Line Items]
Regulatory liabilities-current		38	54
Regulatory liabilities-noncurrent		105	45
Virginia Electric and Power Company | Nuclear decommissioning trust
Regulatory Liabilities [Line Items]
Regulatory liabilities-noncurrent	[5]	1,034	902
Virginia Electric and Power Company | Derivatives
Regulatory Liabilities [Line Items]
Regulatory liabilities-noncurrent	[6]	78	69
Virginia Electric and Power Company | Provision for future cost of removal
Regulatory Liabilities [Line Items]
Regulatory liabilities-noncurrent	[4]	985	946
Dominion Energy Gas Holdings, LLC
Regulatory Liabilities [Line Items]
Regulatory liabilities-current	[7]	39	35
Regulatory liabilities-noncurrent	[9]	252	219
Total regulatory liabilities		291	254
Dominion Energy Gas Holdings, LLC | PIPP
Regulatory Liabilities [Line Items]
Regulatory liabilities-current	[3]	20	28
Dominion Energy Gas Holdings, LLC | Other
Regulatory Liabilities [Line Items]
Regulatory liabilities-current		19	7
Regulatory liabilities-noncurrent		74	45
Dominion Energy Gas Holdings, LLC | Provision for future cost of removal and AROs
Regulatory Liabilities [Line Items]
Regulatory liabilities-noncurrent	[4]	$ 178	$ 174

[1] Dominion Energy’s Consolidated Balance Sheet at December 31, 2016 has been derived from the audited Consolidated Balance Sheet at that date.

[2] Reflects deferred fuel expenses for the Virginia and North Carolina jurisdictions of Dominion Energy's and Virginia Power's generation operations.

[3] Under PIPP, eligible customers can make reduced payments based on their ability to pay. The difference between the customer's total bill and the PIPP plan amount is deferred and collected or returned annually under the PIPP rate adjustment clause according to East Ohio tariff provisions.

[4] Rates charged to customers by the Companies' regulated businesses include a provision for the cost of future activities to remove assets that are expected to be incurred at the time of retirement.

[5] Primarily reflects a regulatory liability representing amounts collected from Virginia jurisdictional customers and placed in external trusts (including income, losses and changes in fair value thereon) for the future decommissioning of Virginia Power's utility nuclear generation stations, in excess of the related AROs.

[6] For jurisdictions subject to cost-based rate regulation, changes in the fair value of derivative instruments result in the recognition of regulatory assets or regulatory liabilities as they are expected to be recovered from or refunded to customers.

[7] Current regulatory liabilities are presented in other current liabilities in Virginia Power’s and Dominion Energy Gas’ Consolidated Balance Sheets.

[8] Virginia Power’s Consolidated Balance Sheet at December 31, 2016 has been derived from the audited Consolidated Balance Sheet at that date.

[9] Noncurrent regulatory liabilities are presented in other deferred credits and other liabilities in Dominion Energy Gas' Consolidated Balance Sheets