Energy Supply Agreements Amount

No definition available.

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- Definition

Related Party Transaction, Interconnection Agreement, Optional Termination Period

+ References

No definition available.

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- Definition

Related Party Transaction, Support Services Agreement, Optional Termination Period

+ References

No definition available.

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- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

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-Publisher FASB
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- Definition

The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

+ References

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- Definition

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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- Definition

Amount of transactions with related party during the financial reporting period.

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- 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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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Related Party Transactions (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2019
Related Party Transaction [Line Items]
Interconnection agreement, optional termination period	3 years
Ameren Illinois Capacity Supply Agreements with Ameren Missouri \| Ameren Illinois Company \| 2021 Procurements
Related Party Transaction [Line Items]
Energy Supply Agreements Amount	$ 2
Ameren Services Support Services Agreement
Related Party Transaction [Line Items]
Support services agreement, optional termination period	60 days
Ameren Services Support Services Agreement \| Ameren Illinois Company
Related Party Transaction [Line Items]
Due from Related Parties	$ 80
Ameren Services Support Services Agreement \| Union Electric Company
Related Party Transaction [Line Items]
Due from Related Parties	$ 77
Ameren Missouri Software Licensing with Ameren Illinois \| Ameren Illinois Electric Distribution
Related Party Transaction [Line Items]
Revenue from Related Parties		$ 14
Ameren Missouri Software Licensing with Ameren Illinois \| Ameren Illinois Gas
Related Party Transaction [Line Items]
Revenue from Related Parties		5
Ameren Missouri Software Licensing with Ameren Illinois \| Ameren Illinois Company
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction		24
Capitalized Computer Software, Net		5
Revenue from Related Parties		19
Ameren Missouri Software Licensing with Ameren Illinois \| Union Electric Company
Related Party Transaction [Line Items]
Capitalized Computer Software, Gross		$ 24