Regulatory Matters (Regulatory Matters Narrative - Duke Energy Indiana) (Details) - USD ($)					3 Months Ended		12 Months Ended
	Jul. 28, 2021	Jun. 29, 2020	Dec. 04, 2019	Jul. 02, 2019	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Feb. 03, 2023	Jun. 15, 2022	Dec. 31, 2020
Public Utilities, General Disclosures [Line Items]
Impairment of assets and other charges					$ 8,000,000	$ 215,000,000
Operating Revenues					7,276,000,000	7,011,000,000
Duke Energy Indiana
Public Utilities, General Disclosures [Line Items]
Impairment of assets and other charges						211,000,000
Operating Revenues					$ 975,000,000	822,000,000
Duke Energy Indiana | IURC | Indiana rate case 2019
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease), amount				$ 395,000,000
Requested rate increase, percentage, net of tax			15.60%
Requested rate increase (decrease), amended amount			$ 396,000,000
Approved rate increase (decrease), amount		$ 146,000,000
Rate base										$ 10,200,000,000
Reduction of requested rate increase		$ 200,000,000
Reduction due to depreciation methodology		50.00%
Reduction due to approved return on equity		20.00%
Approved return on equity percentage (as a percent)		9.70%
Requested return on equity (as a percent)		10.40%
Reduction due to earnings adjustments		20.00%
Estimated percentage of total rate increase, step one		75.00%
Estimated percentage of total rate increase, step two	25.00%
Impairment of assets and other charges						211,000,000
Operating Revenues						$ 46,000,000
Regulatory Matters, Settlement To Customers								$ 70,000,000
Duke Energy Indiana | IURC | TDSIG 2.0
Public Utilities, General Disclosures [Line Items]
Future investment in infrastructure									$ 2,000,000,000
Duke Energy Indiana | IURC | Indiana Coal Ash Recovery
Public Utilities, General Disclosures [Line Items]
Impairment of assets and other charges							$ 175,000,000