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

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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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		9 Months Ended
	Apr. 22, 2020	Jan. 24, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Business Acquisition [Line Items]
Acquisition-related costs			$ 4,852,000	$ 0	$ 31,756,000	$ 0
Developed technology
Business Acquisition [Line Items]
Weighted average useful life (in years)					2 years 10 months 24 days
Customer relationships
Business Acquisition [Line Items]
Weighted average useful life (in years)					10 years 6 months
Saba Software, Inc.
Business Acquisition [Line Items]
Equity interest acquired (in percent)	100.00%
Purchase price	$ 1,310,000,000
Cash paid in acquisition	$ 1,277,000,000
Revenue			$ 47,000,000		$ 76,000,000
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