Financing and Leases - Georgia Power Lease Modification (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Lessor, Lease, Description [Line Items]
Operating lease right-of-use assets, net of amortization	$ 1,415	$ 1,432
GEORGIA POWER CO
Lessor, Lease, Description [Line Items]
Operating lease right-of-use assets, net of amortization	879	$ 884
GEORGIA POWER CO | Revision of Prior Period, Adjustment
Lessor, Lease, Description [Line Items]
Operating lease right-of-use assets, net of amortization	8
Lease obligations	10
Finance lease ROU assets, net	44
Finance lease obligations	$ 45