Debt Instrument, Unamortized Discount or Premium and Debt Issuance Costs

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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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.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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- Definition

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Long-Term Debt And Equity Financings (Schedule Of Maturities Of Long-Term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Aug. 31, 2022
Debt Instrument [Line Items]
2024	$ 849
2025	300
2026	950
2027	950
2028	940
Thereafter	12,118
Total	16,107
Ameren (parent)
Debt Instrument [Line Items]
2024	450
2025	0
2026	950
2027	500
2028	450
Thereafter	1,500
Total	3,850
Unamortized discount, premium, and debt issuance costs	21
Ameren Missouri
Debt Instrument [Line Items]
2024	350
2025	0
2026	0
2027	400
2028	0
Thereafter	5,649
Total	6,399
Unamortized discount, premium, and debt issuance costs	58
Ameren Illinois
Debt Instrument [Line Items]
2024	0
2025	300
2026	0
2027	0
2028	490
Thereafter	4,498
Total	5,288
Unamortized discount, premium, and debt issuance costs	56
Ameren Transmission Company of Illinois
Debt Instrument [Line Items]
2024	49
2025	0
2026	0
2027	50
2028	0
Thereafter	471
Total	570
Unamortized discount, premium, and debt issuance costs	2
Unsecured Debt \| Ameren Transmission Company of Illinois \| 2.45% Senior unsecured notes due 2036
Debt Instrument [Line Items]
Debt instrument face amount	75	$ 75
Unsecured Debt \| Ameren Transmission Company of Illinois \| 2.45% Senior unsecured notes due 2036 \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Thereafter	30
Unsecured Debt \| Ameren Transmission Company of Illinois \| 2.45% Senior unsecured notes due 2036 \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Thereafter	45
Unsecured Debt \| Ameren Transmission Company of Illinois \| 3.43% Senior unsecured notes due 2050
Debt Instrument [Line Items]
2024			$ 50
Debt instrument face amount	400	$ 400
Unsecured Debt \| Ameren Transmission Company of Illinois \| 3.43% Senior unsecured notes due 2050 \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
2026	49
Unsecured Debt \| Ameren Transmission Company of Illinois \| 3.43% Senior unsecured notes due 2050 \| Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Thereafter	50
Unsecured Debt \| Ameren Transmission Company of Illinois \| 3.43% Senior unsecured notes due 2050 \| Debt Instrument, Redemption, Period Four
Debt Instrument [Line Items]
Thereafter	49
Unsecured Debt \| Ameren Transmission Company of Illinois \| 3.43% Senior unsecured notes due 2050 \| Debt Instrument, Redemption, Period Five
Debt Instrument [Line Items]
Thereafter	50
Unsecured Debt \| Ameren Transmission Company of Illinois \| 3.43% Senior unsecured notes due 2050 \| Debt Instrument, Redemption, Period Six
Debt Instrument [Line Items]
Thereafter	49
Unsecured Debt \| Ameren Transmission Company of Illinois \| 3.43% Senior unsecured notes due 2050 \| Debt Instrument, Redemption, Period Seven
Debt Instrument [Line Items]
Thereafter	77
Unsecured Debt \| Ameren Transmission Company of Illinois \| 3.43% Senior unsecured notes due 2050 \| Debt Instrument, Redemption, Period Eight
Debt Instrument [Line Items]
Thereafter	$ 76