STOCK COMPENSATION PLANS (Details 2) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($) $ / shares shares
Restricted stock units \| Ratably
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted stock units \| Cliff \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted stock units \| Cliff \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Time-Based
Shares
Outstanding unvested at beginning of year (in shares) \| shares	933,312
Granted (in shares) \| shares	482,251
Vested (in shares) \| shares	(111,724)
Forfeited (in shares) \| shares	(21,191)
Outstanding unvested at end of year (in shares) \| shares	1,282,648
Weighted Average Grant-Date Fair Value
Outstanding unvested at beginning of year (in dollars per share) \| $ / shares	$ 36.83
Granted (in dollars per share) \| $ / shares	31.32
Vested (in dollars per share) \| $ / shares	25.08
Forfeited (in dollars per share) \| $ / shares	35.97
Outstanding unvested at end of year (in dollars per share) \| $ / shares	$ 35.80
Total unrecognized compensation cost \| $	$ 34.9
Weighted average period to recognize unrecognized compensation cost	2 years 2 months 23 days
Performance-Based
Shares
Outstanding unvested at beginning of year (in shares) \| shares	389,358
Granted (in shares) \| shares	159,407
Vested (in shares) \| shares	(138,019)
Forfeited (in shares) \| shares	0
Outstanding unvested at end of year (in shares) \| shares	410,746
Weighted Average Grant-Date Fair Value
Outstanding unvested at beginning of year (in dollars per share) \| $ / shares	$ 34.21
Granted (in dollars per share) \| $ / shares	29.18
Vested (in dollars per share) \| $ / shares	25.25
Forfeited (in dollars per share) \| $ / shares	0.00
Outstanding unvested at end of year (in dollars per share) \| $ / shares	$ 35.27
Total unrecognized compensation cost \| $	$ 13.3
Weighted average period to recognize unrecognized compensation cost	2 years 22 days

Unrecognized cost of unvested share-based compensation awards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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