SHARE-BASED AWARDS AND OPTIONS - Restricted, Performance and Leveraged Units Stock Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	7 Months Ended	12 Months Ended
Dec. 31, 2016	Dec. 31, 2017	May 31, 2016	May 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Share-based compensation expense	$ 18,707	$ 39,095	$ 30,809	$ 21,056
Leveraged Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period				3 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested, beginning of period (in shares)	1,606	1,263	1,848	1,754
Granted (in shares)	348	899	461	954
Vested (in shares)	(639)	(858)	(633)	(648)
Forfeited (in shares)	(52)	(78)	(70)	(212)
Nonvested, end of period (in shares)	1,263	1,226	1,606	1,848
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Nonvested, Weighted Average Grant-Date Fair Value, beginning of period (in dollars per share)	$ 37.25	$ 49.55	$ 28.97	$ 22.72
Granted, Weighted Average Grant-Date Fair Value (in dollars per share)	74.26	79.79	57.04	36.21
Vested, Weighted Average Grant-Date Fair Value (in dollars per share)	31.38	39.26	27.55	23.17
Forfeited, Weighted Average Grant-Date Fair Value (in dollars per share)	45.27	59.56	34.69	27.03
Nonvested, Weighted Average Grant-Date Fair Value, end of period (in dollars per share)	$ 49.55	$ 78.29	$ 37.25	$ 28.97
Total fair value of share awards vested in period	$ 20,000	$ 33,700	$ 17,400	$ 15,000
Share-based compensation expense	$ 17,200	35,200	$ 28,800	$ 19,800
Total unrecognized compensation cost		$ 46,100
Total unrecognized compensation cost, weighted average period (in years)		1 year 292 days
Share-based Compensation Award, Number of Tranches \| Restricted Stock and Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years	4 years
Share-based Compensation Award, Number of Tranches \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			28 months
One Year Increment \| Restricted Stock and Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years
Year One \| Leveraged Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of performance units		33.33%
Year Two \| Leveraged Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of performance units		33.33%
Year Three \| Leveraged Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of performance units		33.33%

Share-based Compensation Arrangement by Share-based Payment Award, Award Performance Period

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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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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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, 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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- Definition

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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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Percentage of vesting of share-based compensation awards.

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