FAIR VALUE MEASUREMENTS (Tables)

3 Months Ended

Mar. 31, 2013

Fair Value Disclosures [Abstract]

Table of financial instruments measured at fair value

The following table summarizes the assets and liabilities measured at fair value in the condensed balance sheets:

	Fair Value Measurements
Balance at March 31, 2013	Level 1		Level 2		Level 3		Total
Assets	($ in millions)
Interest rate swaps	$	—	$	7.7	$	—	$	7.7
Commodity forward contracts	—		1.0		—		1.0
Liabilities
Interest rate swaps	$	—	$	9.5	$	—	$	9.5
Commodity forward contracts	0.2		1.1		—		1.3
Earn out	—		—		21.0		21.0
Balance at December 31, 2012
Assets
Interest rate swaps	$	—	$	8.3	$	—	$	8.3
Commodity forward contracts	0.1		7.5		—		7.6
Liabilities
Interest rate swaps	$	—	$	10.2	$	—	$	10.2
Earn out	—		—		42.0		42.0
Balance at March 31, 2012
Assets
Interest rate swaps	$	—	$	11.7	$	—	$	11.7
Liabilities
Interest rate swaps	$	—	$	12.0	$	—	$	12.0
Commodity forward contracts	0.2		4.0		—		4.2
Earn out	—		—		33.1		33.1

Activity summary of financial instruments measure at fair value using level 3 inputs

The following table summarizes the activity for our earn out liability measured at fair value using Level 3 inputs:

	March 31,
	2013			2012
	($ in millions)
Balance at beginning of year	$	42.0		$	49.0
Settlements	(23.2		)	(18.5		)
Unrealized losses included in other expense	2.2			2.6
Balance at end of period	$	21.0		$	33.1

Fair value of debt table

The following table summarizes the fair value measurements of debt and the actual debt recorded on our condensed balance sheets:

	Fair Value Measurements
	Level 1		Level 2		Level 3		Total		Amount recorded on balance sheets
	($ in millions)
Balance at March 31, 2013	$	—	$	591.0	$	153.0	$	744.0	$	701.5
Balance at December 31, 2012	—		605.1		153.0		758.1		713.7
Balance at March 31, 2012	—		403.6		161.0		564.6		535.6