REGULATORY ASSETS AND LIABILITIES

The Company accounts for regulated operations in accordance with ASC Topic 980, Regulated Operations. This topic sets forth the application of GAAP for those companies whose rates are established by or are subject to approval by an independent third party regulator. The provisions of this accounting guidance require, among other things, that financial statements of a regulated enterprise reflect the actions of regulators, where appropriate. These actions may result in the recognition of revenues and expenses in time periods that are different than non-regulated enterprises. When this occurs, costs are deferred as assets in the balance sheet (regulatory assets) and recorded as expenses when those amounts are reflected in rates. Also, regulators can impose liabilities upon a regulated company for amounts previously collected from customers and for recovery of costs that are expected to be incurred in the future (regulatory liabilities).

The following regulatory assets and regulatory liabilities were reflected in the Company's Balance Sheets and also included below:



	September 30, 2014				December 31, 2013
($ Millions)	Current		Noncurrent		Current		Noncurrent
Regulatory assets:
Postretirement assets	$	6.4	$	66.1	$	0.3	$	58.2
Accretion and depreciation for asset retirement obligation	—		18.3		—		18.0
Rate recovery of asset removal costs, net	—		2.8		—		4.7
Enhanced stability reserve	—		3.4		—		4.0
Gas supply adjustment	—		—		2.5		—
RSE adjustment	2.4		—		—		—
Total regulatory assets	$	8.8	$	90.6	$	2.8	$	84.9

Regulatory liabilities:
RSE adjustment	$	19.8	$	—	$	4.7	$	—
Unbilled service margin	5.2		—		28.5		—
Postretirement liabilities	2.3		26.2		—		26.2
Refundable negative salvage	13.4		26.8		15.8		39.7
Gas supply adjustment	22.4		—		—		—
Other	—		0.7		—		0.7
Total regulatory liabilities	$	63.1	$	53.7	$	49.0	$	66.6