Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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BUSINESS COMBINATIONS - Additional Information (Details) - USD ($)			3 Months Ended		6 Months Ended
	Apr. 22, 2020	Jan. 24, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Business Acquisition [Line Items]
Acquisition-related costs			$ 20,093,000	$ 0	$ 26,904,000	$ 0
Developed technology
Business Acquisition [Line Items]
Weighted average useful life (in years)					3 years 2 months 12 days
Customer relationships
Business Acquisition [Line Items]
Weighted average useful life (in years)					10 years 8 months 12 days
Saba Software, Inc.
Business Acquisition [Line Items]
Equity interest acquired (in percent)	100.00%
Purchase price	$ 1,313,000,000
Cash paid in acquisition	$ 1,280,000,000
Revenue			$ 29,400,000
Saba Software, Inc. \| Common Stock
Business Acquisition [Line Items]
Equity interest transferred (in shares)	1,110,352
Equity interest transferred	$ 32,900,000
Expected tax deductible amount of goodwill acquired	$ 0
Clustree
Business Acquisition [Line Items]
Cash paid in acquisition		$ 18,600,000
Clustree \| Developed technology
Business Acquisition [Line Items]
Weighted average useful life (in years)		3 years
Clustree \| Customer relationships
Business Acquisition [Line Items]
Weighted average useful life (in years)		2 years