Acquisitions Acquisitions - Schedule of Consideration Paid to ObjectVideo and Estimated Fair Value of Tangible and Intangible Net Assets Acquired (Details) - USD ($) $ in Thousands	Jan. 01, 2017	Jun. 30, 2017	Dec. 31, 2016
Estimated Tangible and Intangible Net Assets:
Goodwill		$ 64,092	$ 24,723
ObjectVideo
Calculation of Purchase Consideration:
Cash paid, net of working capital adjustment	$ 6,000
Estimated Tangible and Intangible Net Assets:
Current liabilities	(58)
Goodwill	2,658
Total estimated tangible and intangible net assets	6,000
Developed Technology | ObjectVideo
Estimated Tangible and Intangible Net Assets:
Developed technology	$ 3,400