STOCK-BASED COMPENSATION Performance-based Awards and Restricted Stock Units (Details) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($) $ / shares shares
Restricted Stock Units (RSUs)
Shares
Outstanding at January 1, 2020	1,719
Granted	430
Vested	(589)
Forfeited	(30)
Outstanding at September 30, 2020	1,530
Outstanding and expected to vest at September 30, 2020	1,418
Weighted- Average Grant Date Fair Value Per Share (in dollars per share)
Outstanding at January 1, 2020 \| $ / shares	$ 31.33
Granted \| $ / shares	44.48
Vested \| $ / shares	30.16
Forfeited \| $ / shares	36.89
Outstanding at September 30, 2020 \| $ / shares	$ 35.37
Weighted-Average Remaining Contractual Term (In years)
Outstanding at September 30, 2020	1 year 7 months 28 days
Outstanding and expected to vest at September 30, 2020	1 year 7 months 6 days
Aggregate Intrinsic Value (In thousands)
Outstanding at September 30, 2020 \| $	$ 84,733
Outstanding and expected to vest at September 30, 2020 \| $	$ 78,580
Long-Term Performance-Based Awards (PRSUs)
Shares
Outstanding at January 1, 2020	287
Granted	152
Vested	0
Forfeited	0
Outstanding at September 30, 2020	439
Outstanding and expected to vest at September 30, 2020	267
Weighted- Average Grant Date Fair Value Per Share (in dollars per share)
Outstanding at January 1, 2020 \| $ / shares	$ 32.03
Granted \| $ / shares	49.67
Vested \| $ / shares	0
Forfeited \| $ / shares	0
Outstanding at September 30, 2020 \| $ / shares	$ 38.14
Weighted-Average Remaining Contractual Term (In years)
Outstanding at September 30, 2020	1 year 3 months
Outstanding and expected to vest at September 30, 2020	1 year 9 months 25 days
Aggregate Intrinsic Value (In thousands)
Outstanding at September 30, 2020 \| $	$ 24,345
Outstanding and expected to vest at September 30, 2020 \| $	$ 14,816
Performance Based Awards (PSUs)
Shares
Outstanding at January 1, 2020	121
Granted	149
Vested	(121)
Forfeited	0
Outstanding at September 30, 2020	149
Outstanding and expected to vest at September 30, 2020	140
Weighted- Average Grant Date Fair Value Per Share (in dollars per share)
Outstanding at January 1, 2020 \| $ / shares	$ 35.06
Granted \| $ / shares	46.25
Vested \| $ / shares	35.06
Forfeited \| $ / shares	0
Outstanding at September 30, 2020 \| $ / shares	$ 46.21
Weighted-Average Remaining Contractual Term (In years)
Outstanding at September 30, 2020	3 months
Outstanding and expected to vest at September 30, 2020	3 months
Aggregate Intrinsic Value (In thousands)
Outstanding at September 30, 2020 \| $	$ 8,235
Outstanding and expected to vest at September 30, 2020 \| $	$ 7,733
Minimum [Member] \| Long-Term Performance-Based Awards (PRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Performance Based Awards Shares Released As Percentage Of Target Number	0.00%
Minimum [Member] \| Performance Based Awards (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Performance Based Awards Shares Released As Percentage Of Target Number	0.00%
Maximum [Member] \| Long-Term Performance-Based Awards (PRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Performance Based Awards Shares Released As Percentage Of Target Number	200.00%
Maximum [Member] \| Performance Based Awards (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Performance Based Awards Shares Released As Percentage Of Target Number	200.00%

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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 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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for equity-based awards excluding options, 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 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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