Business Combinations - Additional Information (Details) $ in Millions	3 Months Ended
Jul. 31, 2018 USD ($)
Three Privately-held Technology Companies
Business Acquisition [Line Items]
Business acquisition, aggregate consideration paid	$ 2.4

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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