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.

+ References

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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.

+ References

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- Definition

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

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- Definition

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

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

+ Details

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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.

+ Details

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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- 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.

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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.

+ Details

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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

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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)				3 Months Ended
	Dec. 23, 2019 USD ($)	Dec. 02, 2019 USD ($)	Nov. 12, 2019 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 14, 2016 bank
Line of Credit Facility [Line Items]
Long-term Debt				$ 975,000,000.0
Credit facility borrowings				$ 0	$ 0	$ 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]
Short-term borrowings used to support lending to Utilities				$ 373,200,000
Spire Missouri \| 2.84% Series, due November 15, 2029
Line of Credit Facility [Line Items]
Long-term debt			$ 275,000,000.0
Stated interest rate			2.84%
Debt instrument, maturity date			Nov. 15, 2029
Spire Missouri \| Floating-Rate Note
Line of Credit Facility [Line Items]
Repayment of long-term debt			$ 100,000,000.0
Spire Alabama \| Series 2019B Senior Notes due 2029 \| Senior Notes \| Private Placement
Line of Credit Facility [Line Items]
Long-term debt		$ 100,000,000.0
Stated interest rate		2.88%
Debt instrument, maturity date		Dec. 01, 2029
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				0.55
Revolving Credit Facility Borrowings \| Spire
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity				$ 300,000,000.0
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				0.50
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				0.41
Commercial Paper Notes
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity				$ 975,000,000.0
Debt term				365 days