BALANCE SHEET DETAILS - Prepaid Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Prepaid expenses	$ 816	$ 933
Contract assets - current	11,623	13,128
Other current assets	171	17
Prepaid expenses and other current assets	$ 12,610	$ 14,078

Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Name:	us-gaap_PrepaidExpenseCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant