Line Of Credit Facility, Number Of Banks In Agreement

No definition available.

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- Definition

Line of credit debt covenant required earnings before interest, taxes, depreciation, and amortization (EBITDA) minimum times interest expense

+ References

No definition available.

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- Definition

Short-term borrowings used to support lending to Utilities

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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- Definition

The average effective interest rate during the reporting period.

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- Definition

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

+ References

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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

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- Definition

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

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- Definition

Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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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

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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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

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Financing Arrangements and Long-term Debt - Additional Information (Details)					6 Months Ended
	Mar. 26, 2020 USD ($) bank	Dec. 23, 2019 USD ($)	Dec. 02, 2019 USD ($)	Nov. 12, 2019 USD ($)	Mar. 31, 2020 USD ($)	Dec. 14, 2016 bank
Line of Credit Facility [Line Items]
Long-term Debt					$ 975,000,000.0
Private Placement \| Spire STL Pipeline LLC
Line of Credit Facility [Line Items]
Debt term		9 years 2 months 12 days
Long-term debt		$ 135,000,000.0
Stated interest rate		2.95%
Debt instrument, payment terms					Interest is payable semi-annually at 2.95%, and principal repayment is scheduled annually in accordance with a 15-year amortization schedule with an average life of 9.2 years.
Debt instrument, amortization period		15 years
Liabilities \| Lender Concentration Risk
Line of Credit Facility [Line Items]
Line of credit facility, number of banks in agreement \| bank						11
Spire
Line of Credit Facility [Line Items]
Term loan bear interest rate per annum					2.10%
Short-term borrowings used to support lending to Utilities					$ 91,700,000
Spire \| Term Loan
Line of Credit Facility [Line Items]
Line of credit facility, number of banks in agreement \| bank	2
Long-term Debt	$ 150,000,000.0
Debt instrument, maturity date	Mar. 25, 2021
Team loan interest rate description					The term loan bears interest at the LIBOR Rate (as defined in the loan agreement) plus 0.85% per annum.
Term loan bear interest rate per annum					2.10%
Spire \| Term Loan \| LIBOR
Line of Credit Facility [Line Items]
Term loan bear interest rate per annum	0.85%
Spire Missouri \| 2.84% Series, due November 15, 2029
Line of Credit Facility [Line Items]
Debt instrument, maturity date				Nov. 15, 2029
Long-term debt				$ 275,000,000.0
Stated interest rate				2.84%
Spire Missouri \| Floating-Rate Note
Line of Credit Facility [Line Items]
Repayment of long-term debt				$ 100,000,000.0
Spire Alabama \| Senior Notes \| Series 2019B Senior Notes due 2029 \| Private Placement
Line of Credit Facility [Line Items]
Debt instrument, maturity date			Dec. 01, 2029
Long-term debt			$ 100,000,000.0
Stated interest rate			2.88%
Debt instrument, payment terms					Interest is payable semi-annually.
Revolving Credit Facility Borrowings
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity					$ 975,000,000.0
Minimum required ratio of earnings before interest, taxes, depreciation, and amortization (EBITDA) times interest expense as required by the line of credit covenant					70.00%
Debt to total capitalization ratio					0.54
Revolving Credit Facility Borrowings \| Spire
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity					$ 300,000,000.0
Term loan bear interest rate per annum					1.90%
Revolving Credit Facility Borrowings \| Spire Missouri
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity					$ 475,000,000.0
Debt to total capitalization ratio					0.45
Term loan bear interest rate per annum					1.80%
Revolving Credit Facility Borrowings \| Spire Alabama
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity					$ 200,000,000.0
Debt to total capitalization ratio					0.34
Term loan bear interest rate per annum					1.80%
Commercial Paper Notes
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity					$ 975,000,000.0
Debt term					365 days
Commercial Paper Notes \| Spire
Line of Credit Facility [Line Items]
Term loan bear interest rate per annum					2.10%