Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets
Cash and cash equivalents	$ 126,574	$ 185,094
Marketable securities	85,010
Restricted cash	749	749
Trade receivables, (including related parties of $4,391 and $8,162) net of allowance for doubtful accounts of $6,293 and $6,398	173,419	201,747
Assets held for sale	1,963	1,963
Prepaid expenses and other current assets (including related parties of $274 and $274)	36,341	18,925
Total current assets	424,056	408,478
Property and equipment, net of accumulated depreciation of $187,293 and $183,930	60,174	62,498
Intangible assets subject to amortization, net of accumulated amortization of $107,251 and $104,687 (including related parties of $4,410 and $4,642)	61,476	64,034
Intangible assets not subject to amortization	209,053	209,053
Goodwill	71,708	71,708
Deferred income taxes	1,462	1,462
Operating leases right of use asset	25,596	25,582
Other assets	8,084	8,527
Total assets	861,609	851,342
Current liabilities
Current maturities of long-term debt	4,947	4,903
Accounts payable and accrued expenses (including related parties of $1,342 and $1,920)	222,610	212,655
Operating lease liabilities	6,808	7,304
Total current liabilities	234,365	224,862
Long-term debt, less current maturities, net of unamortized debt issuance costs of $1,684 and $1,851	206,816	207,416
Long-term operating lease liabilities	21,505	20,988
Other long-term liabilities	79,076	72,930
Deferred income taxes	68,092	68,220
Total liabilities	609,854	594,416
Commitments and contingencies (note 6)
Stockholders' equity
Additional paid-in capital	773,613	780,388
Accumulated deficit	(520,607)	(522,494)
Accumulated other comprehensive income (loss)	(1,260)	(977)
Total stockholders' equity	251,755	256,926
Total liabilities and stockholders' equity	861,609	851,342
Class A common stock
Stockholders' equity
Common stock	6	6
Class B common stock
Stockholders' equity
Common stock	2	2
Class U common stock
Stockholders' equity
Common stock	$ 1	$ 1