SEGMENT REPORTING (Details) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2020 USD ($) operating_segments	Jun. 30, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of business segments | operating_segments					2
Reconciliation of EBITDA to net income (loss) [Abstract]
Net income	$ 60,360	$ 72,793	$ 63,248	$ 85,169	$ 133,153	$ 148,417
Amortization of acquired intangible assets in cost of revenues	6,054		5,033		12,059	10,546
Amortization of acquired intangible assets in operating expenses	14,935		7,175		26,419	14,857
Depreciation and other amortization	6,990		6,546		13,757	13,010
Interest expense (income)	3,596		(4,678)		1,945	(8,890)
Other expense (income)	474		(538)		(367)	(539)
Income tax expense	16,889		16,768		22,452	29,304
EBITDA	109,298		93,554		209,418	206,705
North America [Member]
Reconciliation of EBITDA to net income (loss) [Abstract]
EBITDA	112,292		95,001		214,705	210,269
International [Member]
Reconciliation of EBITDA to net income (loss) [Abstract]
EBITDA	$ (2,994)		$ (1,447)		$ (5,287)	$ (3,564)