Valuation And Qualifying Accounts (Details) - USD ($) $ in Thousands		12 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Valuation and Qualifying Accounts [Abstract]
Balance at Beginning of Period		$ 31,811	$ 27,144	$ 30,317
Additions Charged to Costs and Expenses		9,316	10,856	5,568
Additions Charged to Other Accounts	[1]	2,585	3,241	2,390
Deductions	[2]	14,683	9,430	11,131
Balance at End of Period		$ 29,029	$ 31,811	$ 27,144

[1] Represents the discount on accounts receivable purchased in accordance with the Utility segment’s 2005 New York rate agreement.

[2] Amounts represent net accounts receivable written-off.