INCOME TAXES - Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal statutory tax rate	21.00%	21.00%	35.00%
Increase (decrease) in the tax rate resulting from:
State taxes, net of federal effect	4.20%	2.40%	5.20%
Foreign operations, net	2.50%	0.70%	(0.90%)
Research and development tax credits	(1.10%)	(1.10%)	(1.30%)
Tax Act	0.00%	(3.20%)	(33.90%)
Return to provision adjustments	(3.70%)	1.10%	(0.50%)
Change in valuation allowance against deferred tax assets	(0.30%)	0.00%	(3.30%)
Other	3.20%	4.50%	(2.30%)
Effective Income Tax Rate Reconciliation, Percent	25.80%	25.40%	(2.00%)