Income Taxes (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013
Income Taxes [Line Items]
Taxes refundable to customers	$ 84,781,000	$ 85,655,000
Recoverable future taxes	162,296,000	163,355,000
Tax benefit recorded from exercise of stock options	3,100,000	700,000
Tax Benefit Not Realized Due to Tax Loss Carryforward	36,400,000	36,400,000
Amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate	2,000,000
Change in unrecognized tax benefits	2,000,000
Deferred Income Taxes [Member]
Income Taxes [Line Items]
Taxes refundable to customers	84,800,000	85,700,000
Recoverable future taxes	$ 162,300,000	$ 163,400,000