Revenue from Contracts with Customers (Tables)

6 Months Ended

Jun. 30, 2018

Revenue From Contract With Customer [Abstract]

Summary of Changes in Deferred Revenue Balance for Product and Service Revenue

A summary of changes in deferred revenue balances for product and service revenue is as follows:

	Product Revenue			Service Revenue			Total
Opening Balance - December 31, 2017	$	5,888		$	253		$	6,141
Additions		300			917			1,217
Recognized into Revenue		(230	)		(538	)		(768	)
Recognized into Accumulated Deficit		(5,703	)		—			(5,703	)
Ending Balance - June 30, 2018	$	255		$	632		$	887