SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 3,534	$ 2,622	$ 1,231
Charged to Expense	3,601	454	2,171
(Uncollectible Accounts Written Off, Net of Recoveries)	2,255	(457)	(780)
Balance at End of Period	$ 4,880	$ 3,534	$ 2,622