INCOME TAXES - Unrecognized Tax Benefits Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1	$ 909	$ 935	$ 1,025
Additions based on tax positions related to the current year	190	177	149
Additions based on tax positions taken in prior years	180	0	0
Decreases based on the expiration of statute of limitations	(213)	(203)	(239)
Balance at December 31	$ 1,066	$ 909	$ 935