Condensed Consolidated Statements of Comprehensive Income (unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Net income	$ 45,286	$ 36,812
Net gains in fair value of derivative instruments (net of tax of $0 and $(1,799), respectively)	0	2,537
Reclassifications of net losses on derivative instruments (net of tax of $(278) and $(84), respectively)	391	119
Benefit plans reclassifications of actuarial losses and prior service costs (net of tax of $(70) and $(139), respectively)	98	195
Other comprehensive income	489	2,851
Comprehensive income	$ 45,775	$ 39,663