Utility Regulatory Assets and Liabilities and Regulatory Matters (Tables)

12 Months Ended

Sep. 30, 2012

Regulated Operations [Abstract]

Regulatory assets and liabilities associated with Gas Utility and Electric Utility

The following regulatory assets and liabilities associated with Utilities are included in our accompanying balance sheets at September 30:

	2012		2011
Regulatory assets:
Income taxes recoverable	$	103.2	$	97.9
Underfunded pension and postretirement plans	188.2		150.7
Environmental costs	16.8		19.5
Deferred fuel and power costs	11.6		12.2
Removal costs, net	12.7		12.3
Other	5.9		7.8
Total regulatory assets	$	338.4	$	300.4
Regulatory liabilities:
Postretirement benefits	$	13.1	$	11.5
Environmental overcollections	2.9		4.7
Deferred fuel and power refunds	4.4		6.6
State tax benefits — distribution system repairs	7.4		6.3
Other	0.5		0.7
Total regulatory liabilities	$	28.3	$	29.8