INCOME TAXES (Summary of Effective Tax Rate) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Schedule of Effective Tax Rate [Line Items]
Reported tax rate	7.30%	0.40%	19.80%	16.70%
Effective tax rate estimate			20.50%
U.S. statutory income tax rate			35.00%	35.00%
Income tax expense, tax benefit due to release of tax contingency reserves	$ 2.1		$ 2.1
Income tax expense, tax benefit due to change in state tax law	0.2		0.2
Income tax expense, tax contingency settlement	0.2
Deferred Income Tax Charges [Member]
Schedule of Effective Tax Rate [Line Items]
Income tax expense, correction to deferred tax asset in current period relating to 2009				1.7
State and Local Jurisdiction [Member]
Schedule of Effective Tax Rate [Line Items]
Income tax expense, state tax law change				0.7