SHAREHOLDERS' EQUITY - Employee Stock Purchase Plan (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Class of Stock [Line Items]
Espp Shares Market Value	85.00%		85.00%
Employee stock ownership plan (ESOP) (in shares)	1,000		1,000
ESPP share discount	15.00%		15.00%
Non-cash compensation expense recognized	$ 2,444	$ 3,393	$ 4,224	$ 6,966
Employee Stock Purchase Plan
Class of Stock [Line Items]
Number of shares purchased (in shares)			166	159
Non-cash compensation expense recognized			$ 43	$ 131

Percentage of discount rate related to ESPP Shares.

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- Definition

Percentage of market value of ESPP Shares.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

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.

+ References

No definition available.

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- Definition

The shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. IRS rules require allocations to be nondiscriminatory generally based on compensation, length of service, or a combination of both. For any particular participant such shares or units may be vested, unvested, or partially vested.

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- Definition

Number of shares of capital stock issued (purchased by employees) in connection with an employee stock ownership plan.

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