CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Sep. 30, 2014
Assets
Non-utility property (net of accumulated depreciation and amortization)	$ 7.2	$ 6.7
Capitalization:
Common stock, par value (in dollars per share)	$ 1.00	$ 1.00
Common stock, authorized (in shares)	70,000,000us-gaap_CommonStockSharesAuthorized	70,000,000us-gaap_CommonStockSharesAuthorized
Common stock, issued (in shares)	43,300,000us-gaap_CommonStockSharesIssued	43,200,000us-gaap_CommonStockSharesIssued
Common stock, outstanding (in shares)	43,300,000us-gaap_CommonStockSharesOutstanding	43,200,000us-gaap_CommonStockSharesOutstanding
Laclede Gas
Capitalization:
Common stock, par value (in dollars per share)	$ 1.00	$ 1.00
Common stock, authorized (in shares)	50,000	50,000
Common stock, issued (in shares)	24,577	24,577
Common stock, outstanding (in shares)	24,577	24,577
Alagasco
Capitalization:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	3,000,000	3,000,000
Common stock, issued (in shares)	2,000,000	2,000,000
Common stock, outstanding (in shares)	2,000,000	2,000,000

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Face amount or stated value per share of common stock.

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