Debt Securities Issues

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The percent of par value that debt was issued/redeemed for.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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- Definition

Description of debt redemption features under terms of the debt agreement.

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- Definition

Amount, after accumulated amortization, of debt discount (premium).

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- Definition

Amount of long-term debt classified as other, payable within one year or the operating cycle, if longer.

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- Definition

Amount of cash outflow for the payment of debt classified as other, maturing after one year or the operating cycle, if longer.

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- Definition

The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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- Definition

Carrying value as of the balance sheet date of the portion of long-term, uncollateralized debt obligations due within one year or the normal operating cycle, if longer.

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- Definition

Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Debt and Other Obligations Debt and Other Obligations - Debt Securities Activity (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2013
Debt Instrument
Face Amount	$ 40			$ 360
Discount on debt issues	(9)	$ (8)
Redemptions/Maturities of variable interest entities	35	39	$ 43
Redemptions/Maturities of power bonds	$ 1,022	$ 29	$ 1,028
Percent of par value	99.109%	99.187%
Total Current maturities of power bonds issued at par	$ 1,022	$ 1,022
Short-term debt, net of discounts	1,167	432
Current maturities of long-term debt of variable interest entities issued at par	37	35
Long-term power bonds, net	17,867	17,844
880591EF5 (12.15.20)
Debt Instrument
Total Current maturities of power bonds issued at par	$ 1	1
Interest rate	3.77%
Debt Instrument, Maturity Date	Dec. 15, 2024
880591EF5 (6.15.21)
Debt Instrument
Total Current maturities of power bonds issued at par	$ 21	21
Interest rate	3.77%
Debt Instrument, Maturity Date	Jun. 15, 2025
880591ER9
Debt Instrument
Total Current maturities of power bonds issued at par	$ 0	1,000
Interest rate	2.875%
Debt Instrument, Maturity Date	Sep. 15, 2024
880591EW8 [Member]
Debt Instrument
Total Current maturities of power bonds issued at par	$ 1,000	$ 0
Interest rate	0.75%
Debt Instrument, Maturity Date	May 15, 2025
Total
Debt Instrument
Debt Instrument, Redemption Period, End Date	1,057	68
Percent of par value	100.00%
Debt of variable interest entities
Debt Instrument
Redemptions/Maturities of variable interest entities	$ 35	$ 39
2009 Series B
Debt Instrument
Redemptions/Maturities of power bonds	22	29
2012 Series A
Debt Instrument
Redemptions/Maturities of power bonds	1,000	0
Total
Debt Instrument
Debt Securities Issues	$ 991	992
880591EY4
Debt Instrument
Interest rate	4.25%
Debt Instrument, Maturity Date	Sep. 15, 2052
Long-term power bonds, net	$ 500	500
880591EX6
Debt Instrument
Interest rate	1.50%
Debt Instrument, Maturity Date	Sep. 15, 2031
Long-term power bonds, net	$ 500	500
880591EZ1
Debt Instrument
Face Amount	$ 0	1,000
Interest rate	3.875%
Debt Instrument, Maturity Date	Mar. 15, 2028
Long-term power bonds, net	$ 1,000	1,000
880591FB3
Debt Instrument
Interest rate	4.375%
Debt Instrument, Maturity Date	Aug. 01, 2034
Long-term power bonds, net	$ 1,000	$ 0