SEGMENTS INFORMATION (Reconciliation of Segment Operating Profit to Consolidated Income Before Provision for Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment operating profit	$ 87,509	$ 64,658
Stock-based compensation expense	11,881	21,856
Interest and other income, net	2,386	3,076
Foreign exchange gain/(loss)	6,524	(3,484)
Income before provision for income taxes	96,419	64,250
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment operating profit	111,225	96,831
Unallocated Amounts
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Stock-based compensation expense	(11,881)	(21,856)
Amortization of intangibles assets	(3,135)	(2,138)
Other acquisition-related expenses	(468)	(511)
Other unallocated costs	$ (8,232)	$ (7,668)

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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