Short-term Debt	9 Months Ended
Jun. 30, 2013
Debt Disclosure [Abstract]
Short-term Debt	Short-term Debt Our short-term debt obligations are comprised of commercial paper borrowings. Commercial paper borrowings outstanding were $220.0 million at June 30, 2013 and $157.0 million at September 30, 2012. At June 30, 2013, the weighted average interest rate and maturity period of the commercial paper outstanding were 0.18 percent and fifteen days, respectively. At September 30, 2012, the weighted average interest rate and maturity period of the commercial paper outstanding were 0.27 percent and six days, respectively.

Short-term Debt

9 Months Ended

Jun. 30, 2013

Our short-term debt obligations are comprised of commercial paper borrowings. Commercial paper borrowings outstanding were $220.0 million at June 30, 2013 and $157.0 million at September 30, 2012. At June 30, 2013, the weighted average interest rate and maturity period of the commercial paper outstanding were 0.18 percent and fifteen days, respectively. At September 30, 2012, the weighted average interest rate and maturity period of the commercial paper outstanding were 0.27 percent and six days, respectively.