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STOCK-BASED COMPENSATION PLANS, Summary of Stock Options Outstanding (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) $ / shares shares
Options [Abstract]
Options outstanding, shares (in shares) | shares	1,708,296
Options outstanding, weighted-average exercise price (in dollars per share)	$ 34.57
Options outstanding, weighted-average remaining life	6 years 7 days
Options exercisable, shares (in shares) | shares	1,015,823
Options exercisable, weighted-average exercise price (in dollars per share)	$ 29.57
Weighted-average remaining contractual term of outstanding stock options	6 years 7 days
Weighted-average remaining contractual term of outstanding and exercisable stock options	4 years 10 months 6 days
Aggregate intrinsic value of outstanding stock options | $	$ 33.4
Aggregate intrinsic value of exercisable stock options | $	$ 24.6
$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
Exercise price range, upper range limit (in dollars per share)	$ 18.00
Options [Abstract]
Options outstanding, shares (in shares) | shares	24,736
Options outstanding, weighted-average exercise price (in dollars per share)	$ 17.82
Options outstanding, weighted-average remaining life	1 year 3 months 22 days
Options exercisable, shares (in shares) | shares	24,736
Options exercisable, weighted-average exercise price (in dollars per share)	$ 17.82
$18.001 - $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)	18.001
Exercise price range, upper range limit (in dollars per share)	$ 28.00
Options [Abstract]
Options outstanding, shares (in shares) | shares	314,511
Options outstanding, weighted-average exercise price (in dollars per share)	$ 22.23
Options outstanding, weighted-average remaining life	2 years 11 months 5 days
Options exercisable, shares (in shares) | shares	314,511
Options exercisable, weighted-average exercise price (in dollars per share)	$ 22.23
$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) | shares	171,083
Options outstanding, weighted-average exercise price (in dollars per share)	$ 28.78
Options outstanding, weighted-average remaining life	4 years 2 months 19 days
Options exercisable, shares (in shares) | shares	171,083
Options exercisable, weighted-average exercise price (in dollars per share)	$ 28.78
$29.001 - $30.00 [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)	29.001
Exercise price range, upper range limit (in dollars per share)	$ 30.00
Options [Abstract]
Options outstanding, shares (in shares) | shares	228,668
Options outstanding, weighted-average exercise price (in dollars per share)	$ 29.79
Options outstanding, weighted-average remaining life	5 years 2 months 12 days
Options exercisable, shares (in shares) | shares	176,843
Options exercisable, weighted-average exercise price (in dollars per share)	$ 29.79
$30.001 - $40.00 [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)	30.001
Exercise price range, upper range limit (in dollars per share)	$ 40.00
Options [Abstract]
Options outstanding, shares (in shares) | shares	771,781
Options outstanding, weighted-average exercise price (in dollars per share)	$ 37.09
Options outstanding, weighted-average remaining life	7 years 3 months 11 days
Options exercisable, shares (in shares) | shares	317,005
Options exercisable, weighted-average exercise price (in dollars per share)	$ 37.06
$40.001 - $60.00 [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)	40.001
Exercise price range, upper range limit (in dollars per share)	$ 60.00
Options [Abstract]
Options outstanding, shares (in shares) | shares	197,517
Options outstanding, weighted-average exercise price (in dollars per share)	$ 57.02
Options outstanding, weighted-average remaining life	9 years 1 month 20 days
Options exercisable, shares (in shares) | shares	11,645
Options exercisable, weighted-average exercise price (in dollars per share)	$ 57.12

X

- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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