v3.25.4

Debt and Credit Agreements - Summary of Bank Commitments, Credit Facility Borrowings and Available Capacity (Details) - USD ($) $ in Millions	Dec. 31, 2025	Sep. 30, 2025	Dec. 31, 2024	Nov. 30, 2024
Short-term Debt [Line Items]
Aggregate Bank Commitment	$ 9,458		$ 8,958
Facility Draws	0		0
Outstanding Letters of Credit(a)	2,085		2,173
Outstanding Commercial Paper	0		0
Available Capacity	7,361		6,742
Commercial Paper
Short-term Debt [Line Items]
Aggregate Bank Commitment	4,500		4,500
Revolving Credit Facility
Short-term Debt [Line Items]
Aggregate Bank Commitment	4,500	$ 4,500	4,500
Facility Draws	0		0
Outstanding Letters of Credit(a)	40		51
Outstanding Commercial Paper	0		0
Available Capacity	4,460		4,449
Bilaterals
Short-term Debt [Line Items]
Aggregate Bank Commitment	2,350		1,850
Facility Draws	0		0
Outstanding Letters of Credit(a)	1,276		1,095
Outstanding Commercial Paper	0		0
Available Capacity	1,074		755
Accounts Receivable Facility
Short-term Debt [Line Items]
Aggregate Bank Commitment	1,500		1,500	$ 1,100
Facility Draws	0		0
Outstanding Letters of Credit(a)	0		0
Outstanding Commercial Paper	0		0
Available Capacity	1,500		1,500
Liquidity Facility
Short-term Debt [Line Items]
Aggregate Bank Commitment	971		971
Facility Draws	0		0
Outstanding Letters of Credit(a)	647		907
Outstanding Commercial Paper	0		0
Available Capacity	312		21
Liquidity Facility \| No Additional Collateral Posted
Short-term Debt [Line Items]
Outstanding Commercial Paper	959		928
Project Finance
Short-term Debt [Line Items]
Aggregate Bank Commitment	137		137
Facility Draws	0		0
Outstanding Letters of Credit(a)	122		120
Outstanding Commercial Paper	0		0
Available Capacity	15		17
Other Credit Facility
Short-term Debt [Line Items]
Outstanding Letters of Credit(a)	$ 15		$ 15

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for financing purchases of goods acquired for inventory or imminent delivery to a customer.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Details

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Constellation Energy Corp 10-K