Balance Sheet Components - Schedule of Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Prepaid Expense And Other Assets Current [Abstract]
Unbilled contract assets	$ 0	$ 180,000
Deferred revenues from associated contracts	0	(54,790)
Net unbilled contract assets	0	125,210
Prepaid assets	4,429	6,464
Other current assets	2,052	1,717
Total prepaid expenses and other current assets	$ 6,481	$ 133,391

Supplies, net.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of current assets classified as other.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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