STOCK-BASED COMPENSATION PLANS (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	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 (in shares)	1,374,520
Term of options	10 years
Options vesting period	5Y
Options [Abstract]
Options outstanding, Shares (in shares)	2,760,723
Options outstanding, Weighted-average Exercise Price (in dollars per share)	$ 22.86
Options outstanding, Weighted-average Remaining Life (years)	5.38
Options exercisable, Shares (in shares)	1,977,858
Options exercisable, Weighted-average Exercise Price (in dollars per share)	$ 22.27
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)	4.4
Aggregate intrinsic value of outstanding stock options	$ 12.9
Aggregate intrinsic value of exercisable stock options	10.2
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)	$ 6.40	$ 6.69	$ 5.56
Assumptions [Abstract]
Weighted-average expected life (in years)	7.40	7.72	7.68
Future dividend yield (in hundredths)	3.90%	3.90%	3.00%
Share price volatility (in hundredths)	31.79%	32.12%	32.03%
Weighted-average risk-free interest rate (in hundredths)	2.34%	3.34%	3.66%
Unrecognized stock-based compensation expense	3.2
Period for recognition of unrecognized compensation cost (in years)	5
Total fair value of shares vested	1.7	1.8	3.3
Proceeds from stock option exercises	9.6	5.3
Related tax benefits from stock option exercises	1.1	0.5
Shares issued in connection with stock option exercise (in shares)	479,353	274,330
Total intrinsic value of options exercised	4.9	2.3	3.1
$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 [Abstract]
Options outstanding, Shares (in shares)	195,506
Options outstanding, Weighted-average Exercise Price (in dollars per share)	$ 17.59
Options outstanding, Weighted-average Remaining Life (years)	6.09
Options exercisable, Shares (in shares)	195,506
Options exercisable, Weighted-average Exercise Price (in dollars per share)	$ 17.59
$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 [Abstract]
Options outstanding, Shares (in shares)	1,073,087
Options outstanding, Weighted-average Exercise Price (in dollars per share)	$ 19.73
Options outstanding, Weighted-average Remaining Life (years)	5.56
Options exercisable, Shares (in shares)	748,371
Options exercisable, Weighted-average Exercise Price (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 [Abstract]
Options outstanding, Shares (in shares)	1,138,904
Options outstanding, Weighted-average Exercise Price (in dollars per share)	$ 24.87
Options outstanding, Weighted-average Remaining Life (years)	3.90
Options exercisable, Shares (in shares)	969,262
Options exercisable, Weighted-average Exercise Price (in dollars per share)	$ 24.44
$28.001 - $29.00 [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)	$ 28.001
Exercise price range, upper range limit (in dollars per share)	$ 29.00
Options [Abstract]
Options outstanding, Shares (in shares)	353,226
Options outstanding, Weighted-average Exercise Price (in dollars per share)	$ 28.78
Options outstanding, Weighted-average Remaining Life (years)	9.22
Options exercisable, Shares (in shares)	64,719
Options exercisable, Weighted-average Exercise Price (in dollars per share)	$ 28.78
Stock Options [Member]
Options, Outstanding [Roll Forward]
Outstanding, Beginning Period (in shares)	2,947,215	2,976,892
Granted (in shares)	356,765	274,828
Exercised (in shares)	(526,141)	(282,930)
Forfeited (in shares)	(17,116)	(21,575)
Outstanding, Ending Period (in shares)	2,760,723	2,947,215	2,976,892
Exercisable (in shares)	1,977,858
Weighted-average exercise price of shares [Abstract]
Outstanding, Beginning Period (in dollars per share)	$ 21.43	$ 20.55
Granted (in dollars per share)	$ 28.78	$ 27.36
Exercised (in dollars per share)	$ 18.91	$ 17.97
Forfeited (in dollars per share)	$ 21.47	$ 20.58
Outstanding, Ending Period (in dollars per share)	$ 22.86	$ 21.43	$ 20.55
Exercisable (in dollars per share)	$ 22.27
Stock-based compensation expense related to incentive and non-qualified stock options recognized	1.8	1.8	2.0
Income tax benefit recognized	0.8	0.8	0.9
Restricted Stock [Member]
Weighted-average exercise price of shares [Abstract]
Stock-based compensation expense related to incentive and non-qualified stock options recognized	$ 1.8	$ 2.0	$ 1.6
Restricted Shares [Roll Forward]
Unvested, beginning balance (in shares)	269,641	284,586
Awards (in shares)	64,705	54,958
Forfeitures (in shares)	(2,743)	(9,061)
Vestings (in shares)	(139,520)	(60,842)
Unvested, ending balance (in shares)	192,083	269,641	284,586
Weighted-average grant date fair value [Abstract]
Unvested, beginning balance (in dollars per share)	$ 20.12	$ 18.53
Awards (in dollars per share)	$ 28.77	$ 27.36
Forfeitures (in dollars per share)	$ 23.19	$ 18.91
Vestings (in dollars per share)	$ 18.76	$ 19.40
Unvested, ending balance (in dollars per share)	$ 23.98	$ 20.12	$ 18.53