SHAREHOLDERS' EQUITY - Employee Stock Purchase Plan (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Class of Stock [Line Items]
Non-cash compensation expense recognized	$ 2,612	$ 2,444	$ 5,352	$ 4,224
Employee Stock Purchase Plan
Class of Stock [Line Items]
Number of shares purchased (in shares)			0	166
Non-cash compensation expense recognized			$ 0	$ 43

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

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Balance Type:	na
Period Type:	duration