Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 185,094	$ 119,162
Marketable securities		27,988
Restricted cash	749	749
Trade receivables (including related parties of $8,162 and $6,172), net of allowance for doubtful accounts of $6,398 and $3,790	201,747	142,004
Assets held for sale	1,963	2,141
Prepaid expenses and other current assets (including related parties of $274 and $274)	18,925	18,021
Total current assets	408,478	310,065
Property and equipment, net of accumulated depreciation of $183,930 and $191,183	62,498	72,004
Intangible assets subject to amortization, net of accumulated amortization of $104,687 and $103,752 (including related parties of $4,642 and $5,869)	64,034	49,412
Intangible assets not subject to amortization	209,053	216,653
Goodwill	71,708	58,043
Deferred income taxes	1,462
Operating leases right of use asset	25,582	33,525
Other assets	8,527	7,643
Total assets	851,342	747,345
Current liabilities
Current maturities of long-term debt	4,903	3,000
Accounts payable and accrued expenses (including related parties of $1,920 and $2,087)Accounts payable and accrued expenses	212,655	126,849
Operating lease liabilities	7,304	7,290
Total current liabilities	224,862	137,139
Long-term debt, less current maturities, net of unamortized debt issuance costs of $1,851 and $1,796	207,416	210,454
Long-term operating lease liabilities	20,988	31,775
Other long-term liabilities	72,930	3,732
Deferred income taxes	68,220	54,980
Total liabilities	594,416	438,080
Commitments and contingencies (note 12)
Redeemable noncontrolling interest		33,285
Stockholders' equity
Additional paid-in capital	780,388	828,813
Accumulated deficit	(522,494)	(551,786)
Accumulated other comprehensive income (loss)	(977)	(1,056)
Total stockholders' equity	256,926	275,980
Total liabilities and stockholders' equity	851,342	747,345
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