Energy Services Accounts Receivable Securitization Facility - Trade Receivables Transferred and Sold (Details) - USD ($) $ in Millions		3 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016
Energy Services
Accounts, Notes, Loans and Financing Receivable
Trade receivables transferred to ESFC during the period		$ 246.4	$ 199.3
Energy Services Funding Corporation
Accounts, Notes, Loans and Financing Receivable
ESFC trade receivables sold to the bank during the period		66.0	61.5
ESFC trade receivables - end of period	[1]	81.4	55.4	$ 35.7
Outstanding balance of trade receivables sold		$ 35.0	$ 26.0	$ 25.5

[1] At December 31, 2016, September 30, 2016 and December 31, 2015, the amounts of ESFC trade receivables sold to the bank were $35.0, $25.5 and $26.0, respectively, and are reflected as “short-term borrowings” on the Condensed Consolidated Balance Sheets.