STOCK-BASED COMPENSATION PLANS (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	May 25, 2011
STOCK-BASED COMPENSATION PLANS [Abstract]
Shares of common stock authorized for stock-based compensation plan (in shares)	4,000,000
Additional shares of common stock authorized for stock-based compensation plan ( in shares)				900,000
Number of Shares Available for Grant	1,741,682
Options, Outstanding [Roll Forward]
Exercisable (in shares)	2,199,737
Weighted-average exercise price of shares [Abstract]
Exercisable (in dollars per share)	$ 21.44
Stock-based compensation expense related to incentive and non-qualified stock options recognized	$ 1.8	$ 2.0	$ 2.3
Income tax benefit recognized	0.8	0.9	0.8
Options outstanding [Abstract]
Shares (in shares)	2,947,215
Weighted-average Exercise Price on options outstanding (in dollars per share)	$ 21.43
Weighted-average Remaining Life (years)	5.42
Options exercisable (in shares)	2,199,737
Weighted-average Exercise Price on options outstanding and exercisable (in dollars per share)	$ 21.44
Weighted-average remaining contractual term of outstanding stock options (in years)	5.4
Weighted-average remaining contractual term of outstanding and exercisable stock options (in years)	4.6
Aggregate intrinsic value of outstanding stock options	18.8
Aggregate intrinsic value of outstanding and exercisable stock options	14.0
Fair Value Assumptions and Methodology [Abstract]
Fair Value Assumptions, Method Used	Black-Scholes model	Black-Scholes model	Black-Scholes model
Weighted-average Fair Value of Options Granted (in dollars per share)	$ 6.69	$ 5.56	$ 4.66
Assumptions [Abstract]
Weighted-average expected life (in years)	7.72	7.68	7.77
Future dividend yield (in hundredths)	3.90%	3.00%	3.00%
Share price volatility (in hundredths)	32.12%	32.03%	30.66%
Weighted-average risk-free interest rate (in hundredths)	3.34%	3.66%	2.86%
Unrecognized stock-based compensation expense	2.8
Period for recognition of unrecognized compensation cost (in years)	5
Total fair value of shares vested	1.8	3.3	1.7
Proceeds from stock option exercises	5.3	5.9
Windfall tax benefits from stock option exercises	0.5	0.4
Shares issued in connection with stock option exercise (in shares)	274,330	337,652
Total intrinsic value of options exercised	2.3	3.1	0.6
$0.00 - $18.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (in dollars per share)	$ 0.00
Exercise price range, upper range limit (in dollars per share)	$ 18.00
Options outstanding [Abstract]
Shares (in shares)	428,377
Weighted-average Exercise Price on options outstanding (in dollars per share)	$ 16.84
Weighted-average Remaining Life (years)	4.20
Options exercisable (in shares)	428,377
Weighted-average Exercise Price on options outstanding and exercisable (in dollars per share)	$ 16.84
$18.001 - $23.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (in dollars per share)	$ 18.001
Exercise price range, upper range limit (in dollars per share)	$ 23.00
Options outstanding [Abstract]
Shares (in shares)	1,272,667
Weighted-average Exercise Price on options outstanding (in dollars per share)	$ 19.64
Weighted-average Remaining Life (years)	6.48
Options exercisable (in shares)	741,585
Weighted-average Exercise Price on options outstanding and exercisable (in dollars per share)	$ 20.12
$23.001 - $28.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (in dollars per share)	$ 23.001
Exercise price range, upper range limit (in dollars per share)	$ 28.00
Options outstanding [Abstract]
Shares (in shares)	1,246,171
Weighted-average Exercise Price on options outstanding (in dollars per share)	$ 24.83
Weighted-average Remaining Life (years)	4.76
Options exercisable (in shares)	1,029,775
Weighted-average Exercise Price on options outstanding and exercisable (in dollars per share)	$ 24.30
Stock Options [Member]
Options, Outstanding [Roll Forward]
Outstanding, Beginning Period (in shares)	2,976,892	3,082,815
Granted (in shares)	274,828	352,365
Exercised (in shares)	(282,930)	(411,507)
Forfeited (in shares)	(21,575)	(46,781)
Outstanding, Ending Period (in shares)	2,947,215	2,976,892
Weighted-average exercise price of shares [Abstract]
Outstanding, Beginning Period (in dollars per share)	$ 20.55	$ 20.22
Granted (in dollars per share)	$ 27.36	$ 19.49
Exercised (in dollars per share)	$ 17.97	$ 17.09
Forfeited (in dollars per share)	$ 20.58	$ 21.27
Outstanding, Ending Period (in dollars per share)	$ 21.43	$ 20.55
Restricted Stock [Member]
Weighted-average exercise price of shares [Abstract]
Stock-based compensation expense related to incentive and non-qualified stock options recognized	$ 2.0	$ 1.6	$ 0.8
Restricted Shares [Roll Forward]
Unvested, beginning balance (in shares)	284,586	174,008
Awards (in shares)	54,958	173,341
Forfeitures (in shares)	(9,061)	(9,284)
Vestings (in shares)	(60,842)	(53,479)
Unvested, ending balance (in shares)	269,641	284,586	174,008
Weighted-average grant date fair value [Abstract]
Unvested, beginning balance (in dollars per share)	$ 18.53	$ 18.90
Awards (in dollars per share)	$ 27.36	$ 18.34
Forfeitures (in dollars per share)	$ 18.91	$ 18.17
Vestings (in dollars per share)	$ 19.40	$ 19.19
Unvested, ending balance (in dollars per share)	$ 20.12	$ 18.53	$ 18.90