INCOME TAXES (Details - Income Tax Reconciliation when Applying the Statutory Federal Tax Rate) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal statutory income tax		$ (8,931)	$ 6,506	$ 9,186
State income taxes, net		(3,551)	(1,832)	(14,884)
Excess tax deductions on non-cash compensation		(2,033)	(13,971)	(59,601)
Impact of the Coronavirus Aid, Relief, and Economic Security Act		(6,104)	0	0
Research and experimentation tax credit		(3,800)	(5,794)	(2,523)
Impact of certain state legislation, net		0	3,932	0
Nondeductible executive compensation		1,778	988	163
Change in (release of) valuation allowance		2,100	954	(12)
Uncertain tax positions		458	922	289
Nondeductible meals & entertainment		99	428	310
Impact of Tax Cuts and Jobs Act		0	0	270
Other, net		23	(612)	1,227
Income tax benefit		$ (19,961)	$ (8,479)	(65,575)
Provisional estimate for remeasurement of deferred tax assets and liabilities from Tax Cuts and Jobs Act	$ 9,100			$ 9,100

Effective Income Tax Rate Reconciliation, CARES Act, Amount

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