Revenue Contract Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
COntract Liability Rollforward [Roll Forward]
Contract with Customer, Liability	$ (4,282)	$ (7,066)
Contract with Customer, Liability	(4,855)	(4,282)
Equipment revenue [Member]
COntract Liability Rollforward [Roll Forward]
Increase (Decrease) in Deferred Revenue	(8,807)	(6,696)
Deferred Revenue, Additions	8,794	4,196
Software revenue [Member]
COntract Liability Rollforward [Roll Forward]
Increase (Decrease) in Deferred Revenue	(3,953)	(6,553)
Deferred Revenue, Additions	$ 4,539	$ 6,269