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v3.23.3

Short-term Borrowings and Long-term Debt - Narrative (Details) $ / shares in Units, $ in Millions |  |  | 1 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Oct. 13, 2023 USD ($) numberOfTranche | Aug. 01, 2023 $ / shares | Jul. 31, 2023 USD ($) numberOfSeries | Apr. 30, 2023 USD ($) numberOfSeries | Sep. 30, 2023 USD ($) shares | Sep. 30, 2022 USD ($) | Oct. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Conversion price percentage |  | 25.00% |  |  |  |  |  |
Debt instrument, convertible, conversion ratio |  | 27.1278 |  |  |  |  |  |
Proceeds from long-term debt and term loans |  |  |  |  | $ 5,574 | $ 2,089 |  |
Letters of Credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Long-term line of credit |  |  |  |  | $ 9 |  |  | $ 11
Convertible Debt |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Debt instrument, convertible, conversion price (in dollar per shares) | $ / shares |  | $ 36.86 |  |  |  |  |  |
Debt instrument, redemption price (as a percent) |  | 100.00% |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Debt instrument, convertible, conversion ratio |  |  |  |  | 33.9097 |  |  |
Debt instrument, convertible, number of equity instruments (in shares) | shares |  |  |  |  | 33,909,700 |  |  |
Third Party AMAs |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Inventory financings |  |  |  |  | $ 4 |  |  | 11
CERC |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate Principal Amount |  |  |  |  | 2,000 |  |  |
Proceeds from long-term debt and term loans |  |  |  |  | 2,006 | 852 |  |
CERC | Letters of Credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Long-term line of credit |  |  |  |  | 1 |  |  | 0
CERC | Third Party AMAs |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Inventory financings |  |  |  |  | 4 |  |  | 11
SIGECO |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Proceeds from issuance of secured tax exempt debt |  |  |  | $ 148 |  |  |  |
Debt instrument, series of remarketing agreement to remarket | numberOfSeries |  |  | 2 | 5 |  |  |  |
SIGECO | Letters of Credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Long-term line of credit |  |  |  |  | 0 |  |  | 0
SIGECO | Environmental Improvement Revenue Bonds, Series 2015 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest Rate |  |  | 4.25% |  |  |  |  |
SIGECO | Subsequent Event |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate Principal Amount |  |  |  |  |  |  | $ 470 |
SIGECO | First Mortgage Bonds |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Secured debt |  |  |  |  | $ 457 |  |  |
Percentage of property additions (as a percent) |  |  |  |  | 70.00% |  |  |
Additional first mortgage bonds and general mortgage bonds that could be issued |  |  |  |  | $ 1,400 |  |  |
SIGECO | First Mortgage Bonds | Subsequent Event |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Number of tranches | numberOfTranche | 3 |  |  |  |  |  |  |
Aggregate Principal Amount | $ 470 |  |  |  |  |  |  |
Proceeds from long-term debt and term loans | 467 |  |  |  |  |  |  |
SIGECO | First Mortgage Bonds | Subsequent Event | SIGECO First Mortgage Bonds Due 2029 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate Principal Amount | $ 180 |  |  |  |  |  |  |
Interest Rate | 5.75% |  |  |  |  |  |  |
SIGECO | First Mortgage Bonds | Subsequent Event | SIGECO First Mortgage Bonds Due 2030 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate Principal Amount | $ 105 |  |  |  |  |  |  |
Interest Rate | 5.91% |  |  |  |  |  |  |
SIGECO | First Mortgage Bonds | Subsequent Event | SIGECO First Mortgage Bonds Due 2034 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate Principal Amount | $ 185 |  |  |  |  |  |  |
Interest Rate | 6.00% |  |  |  |  |  |  |
SIGECO | Environmental Improvement Revenue Bonds, Series 2013 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate Principal Amount |  |  |  | $ 107 |  |  |  |
SIGECO | Environmental Improvement Revenue Bonds, Series 2014 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate Principal Amount |  |  |  | $ 41 |  |  |  |
SIGECO | SIGECO First Mortgage Bonds | Nontaxable Municipal Bonds |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Proceeds from issuance of secured tax exempt debt |  |  | $ 38 |  |  |  |  |
SIGECO | Environmental Improvement Revenue Bonds, Series 2015 | Nontaxable Municipal Bonds | Mount Vernon |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate Principal Amount |  |  | 23 |  |  |  |  |
SIGECO | Environmental Improvement Revenue Bonds, Series 2015 | Nontaxable Municipal Bonds | Warrick County |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate Principal Amount |  |  | $ 15 |  |  |  |  |
Houston Electric |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Proceeds from long-term debt and term loans |  |  |  |  | 1,398 | $ 1,589 |  |
Houston Electric | Letters of Credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Long-term line of credit |  |  |  |  | 0 |  |  | $ 0
Houston Electric | General Mortgage Bonds |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate Principal Amount |  |  |  |  | 1,400 |  |  |
Secured debt |  |  |  |  | 7,600 |  |  |
General mortgage bonds used as collateral |  |  |  |  | $ 68 |  |  |
Percentage of property additions (as a percent) |  |  |  |  | 70.00% |  |  |
Additional first mortgage bonds and general mortgage bonds that could be issued |  |  |  |  | $ 4,500 |  |  |
Vectren | Letters of Credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Long-term line of credit |  |  |  |  | 1 |  |  |
Vectren | Maximum | Letters of Credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Long-term line of credit |  |  |  |  | $ 5 |  |  |

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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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