CONCENTRATIONS OF CREDIT RISK	12 Months Ended
CONCENTRATIONS OF CREDIT RISK	Sep. 30, 2018
Risks and Uncertainties [Abstract]
CONCENTRATIONS OF CREDIT RISK	CONCENTRATIONS OF CREDIT RISK Other than in Spire Marketing, Spire has no significant concentration of credit risk. A significant portion of Spire Marketing’s transactions are with (or are associated with) energy producers, utility companies, and pipelines. The concentration of transactions with these counterparties has the potential to affect the Company’s overall exposure to credit risk, either positively or negatively, in that each of these three groups may be affected similarly by changes in economic, industry, or other conditions. To manage this risk, as well as credit risk from significant counterparties in these and other industries, Spire Marketing has established procedures to determine the creditworthiness of its counterparties. These procedures include obtaining credit ratings and credit reports, analyzing counterparty financial statements to assess financial condition, and considering the industry environment in which the counterparty operates. This information is monitored on an ongoing basis. In some instances, Spire Marketing may require credit assurances such as prepayments, letters of credit, or parental guaranties. In addition, Spire Marketing may enter into netting arrangements to mitigate credit risk with counterparties in the energy industry with whom it conducts both sales and purchases of natural gas. Sales are typically made on an unsecured credit basis with payment due the month following delivery. Accounts receivable amounts are closely monitored and provisions for uncollectible amounts are accrued when losses are probable. Spire Marketing records accounts receivable, accounts payable, and prepayments for physical sales and purchases of natural gas on a gross basis. The amount included in accounts receivable attributable to energy producers and their marketing affiliates amounted to $11.2 at September 30, 2018 ($3.7 reflecting netting arrangements). Spire Marketing’s accounts receivable attributable to utility companies and their marketing affiliates comprised $96.1 of total accounts receivable at September 30, 2018 ($89.7 reflecting netting arrangements). Spire Marketing also has concentrations of credit risk with certain individually significant counterparties and with pipeline companies associated with its natural gas receivable amount. At September 30, 2018, the amounts included in accounts receivable from Spire Marketing’s five largest counterparties (in terms of net accounts receivable exposure) totaled $51.3 ($50.6 reflecting netting arrangements). Three of these five counterparties are investment-grade rated integrated utilities. The fourth is an investment-grade rated wholesale power provider. The fifth is not rated, but each of its owners is investment-grade.

Tabular disclosure of all significant concentrations of risk, including credit risk and market risk, arising from all financial instruments (as defined), whether from an individual counterparty or groups of counterparties. The disclosure concerning concentrations of risk may consist of the following information: (1) for concentrations of credit risk disclosure may include: (a) information about the (shared) activity, region, or economic characteristic that identifies the concentration, (b) the maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity, (c) the policy of requiring collateral or other security to support financial instruments subject to credit risk, information about the entity's access to that collateral or other security, and the nature and a brief description of the collateral or other security supporting those financial instruments, and (d) the policy of entering into master netting arrangements to mitigate the credit risk of financial instruments, information about the arrangements for which the entity is a party, and a brief description of the terms of those arrangements, including the extent to which they would reduce the entity's maximum amount of loss due to credit risk and (2) for disclosure of quantitative information about the market risks of financial instruments that is consistent with the way the company manages or adjusts those risks, disclosure may include: (a) more details about current positions and perhaps activity during the period, (b) the hypothetical effects on comprehensive income (or net assets), or annual income, of several possible changes in market prices, (c) a gap analysis of interest rate re-pricing or maturity dates, (d) the duration of the financial instruments, (e) the entity's value at risk from derivatives and from other positions at the end of the reporting period and the average value at risk during the year, or (f) other ways of reporting quantitative information as internally developed.