OTHER CONSOLIDATED BALANCE SHEET COMPONENTS (CURRENT) - Reserve for Transaction Losses (Details) - Transaction Losses - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Loss Contingency Accrual [Roll Forward]
Accrued transaction losses, beginning of the period	$ 70,557	$ 34,771
Provision for transaction losses	(6,742)	79,303
Charge-offs to accrued transaction losses	(15,193)	(17,413)
Accrued transaction losses, end of the period	$ 48,622	$ 96,661

Loss Contingency, Charge-Off And Recoveries

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- Definition

Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

+ Details

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- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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