STOCK AWARD PLANS - Narrative (Details) - USD ($)		9 Months Ended
May 09, 2019	Sep. 30, 2019
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Number of additional shares authorized (shares)	4,000,000
Maximum shares that can be granted under stock plan (shares)		17,041,803
Shares available for stock awards (shares)		5,283,926
Maximum employee contribution to purchase company stock		$ 10,000
Discount rate used to determine the purchase price		15.00%
Stock options
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Stock award, vesting period		5 years
Unrecognized compensation expense		$ 45,000,000.0
Stock awards
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Stock award, vesting period		5 years
Stock awards \| Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Discount on outstanding grants (percent)		15.00%
Stock awards \| Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Discount on outstanding grants (percent)		21.00%
Full value awards
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Unrecognized compensation expense		$ 97,100,000

Compensation Related Costs Share Based Payments Disclosure [Line Items]

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Share based Compensation Arrangement by Share based Payment Award, Maximum Contribution Per Employee

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Discount rate from fair value on purchase date that participants pay for shares.

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Restrictions on equity-based instruments during the vesting period, such as the inability to transfer unvested awards, are not taken into account in estimating the fair value of the award. However, restrictions that remain in effect after an award is vested, such as the inability to transfer or hedge vested options or a prohibition on the sale of outstanding vested shares (or other type of equity) for a period of time, affect the estimate of an award's fair value.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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