Business Combination (Details) - USD ($) $ in Thousands				9 Months Ended	12 Months Ended
	Jan. 10, 2019	Oct. 16, 2018	Apr. 01, 2018	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Purchased Intangible Assets						$ 12,156
Goodwill					$ 7,225	1,549
Total purchase price						13,482
Cash payment to acquire businesses				$ 12,500	13,633	12,482	$ 0
Estimated useful life of technology-based intangible assets				5 years
Layered Insight
Business Acquisition [Line Items]
Purchased Intangible Assets					9,600
Goodwill					5,376
Total purchase price		$ 13,400
Reserve fund		1,600
Business Combination, Additional Consideration		4,000
Business Combination, Earnout Milestone		1,500
Business Combination, Future Payments To Key Employees		$ 4,000
Estimated useful life of technology-based intangible assets		4 years
1Mobility
Business Acquisition [Line Items]
Purchased Intangible Assets					3,700
Goodwill					300
Total purchase price					4,000
Reserve fund					$ 600
Estimated useful life of technology-based intangible assets			4 years
Nevis
Business Acquisition [Line Items]
Purchased Intangible Assets						5,156
Goodwill						583
Total purchase price						5,753
NetWatcher
Business Acquisition [Line Items]
Purchased Intangible Assets						7,000
Goodwill						649
Total purchase price						$ 7,729
Reserve fund				$ 1,000
Future payments for continued employment, year 1				1 year
Future payments for continued employment, year 2				2 years
Subsequent Event
Business Acquisition [Line Items]
Payments For Asset Acquisitions, Payable In Future, Round 1	$ 200
Payments For Asset Acquisitions, Payable In Future, Round 2	600
Subsequent Event | Adya Assets Acquisition [Member]
Business Acquisition [Line Items]
Payments For Asset Acquisitions	$ 1,000