Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Allowances for doubtful accounts	$ 7,637	$ 8,209
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	250,000,000	250,000,000
Common stock, shares issued	79,439,807	78,183,806
Series A Convertible Preferred Stock [Member]
Preferred Stock, par value	$ 0.001	$ 0.001
Preferred Stock, shares authorized	1,000,000	1,000,000
Preferred Stock, shares issued	41,844	40,624
Preferred Stock, shares outstanding	41,844	40,624