Goodwill and Intangible Assets - Additional Information (Details) - USD ($)		12 Months Ended
	Nov. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Intangible Assets And Goodwill [Line Items]
Goodwill		$ 31,328,000	$ 9,676,000	$ 7,839,000
Impairment of goodwill	$ 0	0	0	0
Amortization expense for intangible assets		3,300,000	1,200,000	1,500,000
Developed Technology
Intangible Assets And Goodwill [Line Items]
Amortization expense for intangible assets		$ 1,100,000	$ 200,000	$ 400,000