Fair Value Measurements (Fair Value Measurements Using Unobservable Inputs (Level 3)) (Details) - Derivative Financial Instruments [Member] $ in Thousands	6 Months Ended
	Mar. 31, 2016 USD ($)	[1]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Roll Forward]
Beginning Balance	$ 1,791
Total Gains/Losses, Realized and Included in Earnings	(2,002)	[2]
Total Gains/Losses Unrealized and Included in Other Comprehensive Income (Loss)	211
Transfer In/Out of Level 3	0
Ending Balance	$ 0

[1] Derivative Financial Instruments are shown on a net basis.

[2] Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the three months ended March 31, 2016.