INCOME TAXES - Reconciliation of Effective Income Tax Rate from Statutory Federal Income Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
U.S. federal income taxes at statutory rates	$ (27,717)	$ (26,227)	$ (28,318)
Valuation allowance	(469)	(5,881)	727
State income taxes, net of federal benefit and tax credits	(7,217)	(6,994)	(4,450)
Permanent differences	541	1,773	2,606
Federal research and experimentation credits	(6,380)	(5,716)	(4,295)
Tax effects of foreign activities	3,599	3,050	3,056
Tax-exempt income	0	0	(91)
Provision to return adjustments	(2,016)	3,416	(5,460)
Non-deductible compensation	5,464	1,806	1,716
Expiration of statutes and changes in estimates	(2,250)	55	2,420
Excess tax benefits related to stock-based compensation	(20,697)	(25,797)	(14,291)
Cares Act	0	(10,576)	0
Impact of change in tax law	(11,811)	7,489	1,908
Other	6	86	59
Income tax expense (benefit), total	$ (68,947)	$ (63,516)	$ (44,413)

Effective Income Tax Rate Reconciliation, CARES Act, Amount

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Effective Income Tax Rate Reconciliation Excess Tax Benefits Relating To Share Based Compensation, Amount

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Effective Income Tax Rate Reconciliation, Expiration Of Statutes And Changes In Estimates Amount

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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