Business Combinations - Additional Information (Details) - USD ($) $ in Thousands			12 Months Ended
	Jan. 27, 2017	Dec. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2017	Dec. 31, 2015
Business Acquisition [Line Items]
Purchase price of acquisition, cash			$ 21,235	$ 2,306
Payment of contingent consideration			3,750
Goodwill			$ 31,328	$ 9,676		$ 7,839
Customer Relationships
Business Acquisition [Line Items]
Weighted average useful life of identified acquired intangible assets			5 years
Minimum | Developed Technology
Business Acquisition [Line Items]
Weighted average useful life of identified acquired intangible assets			2 years
Minimum | Tradenames
Business Acquisition [Line Items]
Weighted average useful life of identified acquired intangible assets			2 years
Maximum | Developed Technology
Business Acquisition [Line Items]
Weighted average useful life of identified acquired intangible assets			7 years
Maximum | Tradenames
Business Acquisition [Line Items]
Weighted average useful life of identified acquired intangible assets			7 years
IDV Solutions LLC
Business Acquisition [Line Items]
Date of acquisition of business	Jan. 27, 2017
Purchase price of acquisition, cash	$ 21,200
Escrow deposit	$ 2,500
Escrow deposit period	15 months
Recognition of obligation	$ 5,000		$ 700
Payment of contingent consideration			$ 3,800
Weighted average useful life of identified acquired intangible assets			4 years 3 months 3 days
Goodwill	$ 21,200				$ 21,196
Business acquisition transaction costs			$ 100
IDV Solutions LLC | Developed Technology
Business Acquisition [Line Items]
Weighted average useful life of identified acquired intangible assets			3 years
IDV Solutions LLC | Customer Relationships
Business Acquisition [Line Items]
Weighted average useful life of identified acquired intangible assets			5 years
IDV Solutions LLC | Non-compete Arrangement
Business Acquisition [Line Items]
Weighted average useful life of identified acquired intangible assets			2 years
IDV Solutions LLC | Tradenames
Business Acquisition [Line Items]
Weighted average useful life of identified acquired intangible assets			5 years
IDV Solutions LLC | Minimum
Business Acquisition [Line Items]
Business acquisition, billings threshold date	Jun. 30, 2017
Weighted average life (years)			2 years
IDV Solutions LLC | Maximum
Business Acquisition [Line Items]
Business acquisition, billings threshold date	Dec. 31, 2017
Weighted average life (years)			5 years
Crisis Commander
Business Acquisition [Line Items]
Business acquisition closing date		Dec. 30, 2016
Acquisition, preliminary purchase price		$ 2,700