Subsequent Events - Additional Information (Details) - Usabilla Holding B.V. - Subsequent Event $ in Millions	Apr. 01, 2019 USD ($) shares
Subsequent Event [Line Items]
Closing date of acquisition	Apr. 01, 2019
Estimated total purchase price	$ 84.3
Common stock issued in connection with acquisition \| shares	1,944,211
Payments to acquire businesses gross	$ 54.2

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

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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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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Number of shares of stock issued during the period pursuant to acquisitions.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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