INCOME TAXES - Reconciliation of Effective Income Tax Rate from Statutory Federal Income Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
U.S. federal income taxes at statutory rates	$ (28,318)	$ (2,424)	$ 30,182
Valuation allowance	727	510	459
State income taxes, net of federal benefit and tax credits	(4,450)	(3,329)	(395)
Permanent differences	2,606	1,302	778
GILTI, FDII, and BEAT	0	399	0
Federal research and experimentation credits	(4,295)	(6,991)	(3,374)
Tax effects of foreign activities	3,056	(399)	(781)
Tax-exempt income	(91)	(137)	(94)
Provision to return adjustments	(5,460)	253	(1,832)
Non-deductible compensation	1,716	1,025	1,840
Expiration of statutes and changes in estimates	2,420	(516)	257
Excess tax benefits related to share-based compensation	(14,291)	(13,541)	(24,488)
Impact of change in tax law	1,908	1,636	(15,450)
Other	59	52	585
(Benefit from) income taxes	$ (44,413)	$ (22,160)	$ (12,313)

Effective Income Tax Rate Reconciliation, Changes Due To GILTI, FDII, And BEAT

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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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