Revenue - Schedule of Changes in Deferred Revenue (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2019 USD ($)
Change In Contract With Customer, Liability [Roll Forward]
Balance at December 31, 2018	$ 1,713
Revenue recognized that was included in balance at beginning of the year	(929)
Deferred revenue, net, related to contracts entered into during the year	690
Balance at June 30, 2019	$ 1,474