Receivables From Customers, Net and Notes Receivable, Net Receivables from Customers, Net and Notes Receivables, Net - Bad Debt Expense and Recoveries (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Allowance for Doubtful Accounts Receivable, Period Increase (Decrease)		$ 1.9
Provision for Doubtful Accounts	$ 2.5	2.0
Allowance for Doubtful Accounts Receivable, Write-offs		0.1
Commercial Hedging [Member]
Provision for Doubtful Accounts	$ 2.5	$ 1.7