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Goodwill and Acquired Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 02, 2019
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 54,138		$ 54,138		$ 54,138
Amortization of acquired intangible assets	$ 500	$ 100	$ 1,700	$ 400
Indegy, Ltd
Finite-Lived Intangible Assets [Line Items]
Goodwill						$ 53,900
Intangible assets acquired						$ 15,700