Income Taxes (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Taxes [Line Items]
Income tax expense (benefit)	$ 134	$ 176
Income tax (benefit) expense from discontinued operations	51	56
Cove Point
Income Taxes [Line Items]
Income tax (benefit) expense from discontinued operations		$ 3
East Ohio
Income Taxes [Line Items]
Income tax expense (benefit)	6
Discontinued operations, deferred tax liabilities	29
East Ohio, PSNC and Questar Gas
Income Taxes [Line Items]
Discontinued operations, deferred tax liabilities	825
Questar Gas and Wexpro
Income Taxes [Line Items]
Income tax expense (benefit)	(5)
Discontinued operations, deferred tax liabilities	462
Questar Gas and Wexpro | Enbridge
Income Taxes [Line Items]
Income tax expense (benefit)	$ (22)