Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Consolidated Balance Sheets
Accounts receivable, allowance for doubtful accounts	$ 5,634	$ 5,647
Accumulated depreciation	$ 192,177	$ 193,760
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock shares authorized	1,600,000,000	1,600,000,000
Common stock, shares issued	61,643,718	51,693,931
Common stock, shares outstanding	59,192,012	49,242,225
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	20,000,000	20,000,000
Preferred stock, shares issued	2,779,369	3,290,050
Preferred stock, shares outstanding	2,779,369	3,290,050
Common stock held in treasury at cost (in shares)	2,451,706	2,451,706