Consolidated Comprehensive Income Statement (USD $) In Thousands	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Net Income	$ 105,196	$ 90,258	$ 78,722
Net change in fair value of derivative instruments (net of tax of $7,711)	(10,874)	0	0
Reclassifications of net losses on derivative instruments (net of tax of $(483))	681	681	681
Benefit plans, (net of tax of $479, $11,134 and $29,978, respectively)	(674)	(15,699)	(42,270)
Reclassification of benefit plans actuarial losses and prior service costs (net of tax of $(304), $(2,414) and $(1,617), respectively) to net income	430	3,406	2,281
Reclassification of pension plans actuarial losses and prior service costs (net of tax of $(59,078)) to regulatory assets	0	83,302	0
Comprehensive income	$ 94,759	$ 161,948	$ 39,414