Acquisitions - Acquisition-Related Costs (Details) - TrafficCast International	Dec. 07, 2020 USD ($)
Acquisition
Consideration transferred, assets	$ 16,000,000
Consideration transferred, liabilities	1,700,000
Purchase price	17,700,000
Consideration transferred, cash paid	$ 1,000,000
Consideration transferred, earn out term	2 years

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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