Income Taxes - Components of Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred income tax assets:
Federal net operating loss	$ 76,646	$ 90,032
State net operating loss	56,583	54,074
Foreign net operating loss	17,106	17,452
Research and development expense	290	301
Tax credits	22,938	22,999
Stock options	30,324	26,683
Accruals	10,692	14,779
Equity investments	15,735	13,619
Bad debts	265	310
Lease liability	1,091	861
Foreign credits	9,829	9,819
Available-for-sale securities	2,582	2,473
Operating lease asset	14,554	9,842
Other	6,493	6,393
Deferred income tax assets	265,128	269,637
Deferred income tax liabilities:
Intangible assets	(80,230)	(73,122)
Convertible debt	(6,286)	(10,462)
Operating lease liability	(14,554)	(9,842)
Investment in subsidiaries	(42,140)	0
Fixed assets	(2,592)	(2,736)
Other	(1,638)	(2,082)
Deferred income tax liabilities	(147,440)	(98,244)
Net deferred income tax assets (liabilities)	117,688	171,393
Valuation allowance	(260,397)	(303,326)
Net deferred income tax liabilities	(142,709)	$ (131,933)
Other Assets
Deferred income tax liabilities:
Net deferred income tax liabilities	(4,300)
Assets Held for Sale
Deferred income tax liabilities:
Net deferred income tax liabilities	$ (1,500)