SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - Allowance for doubtful accounts - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deduction from asset accounts:
Balance at Beginning of Period	$ 1,106	$ 1,112	$ 1,038
Charged to Expense	195	15	214
Accounts Written Off	(6)	(21)	(140)
Balance at End of Period	$ 1,295	$ 1,106	$ 1,112