Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Doubtful accounts written off (net)	$ (803)
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Allowance, Beginning Balance	5,197	$ 5,010	$ 5,143
Provision charged to income	1,200	1,347	363
Doubtful accounts written off (net)	(417)	(960)	(416)
Reclassified to assets held for sale (see Note 3)		(152)
Other adjustments	368	(48)	(80)
Allowance, Ending Balance	$ 6,348	$ 5,197	$ 5,010