Segment and Related Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) h segment	Jun. 30, 2018 USD ($)
Segment and Related Information [Abstract]
Number of reportable segments | segment			2
Number of hours of telephone support for restaurant and retail segment | h			24
Information as to the Company's segments [Abstract]
Revenue	$ 44,247	$ 52,571	$ 88,929	$ 108,232
Operating loss	(3,453)	(1,124)	(5,554)	(986)
Other expense, net	(374)	(384)	(804)	(335)
Interest expense, net	(1,244)	(78)	(1,390)	(119)
Loss before benefit from income taxes	(5,071)	(1,586)	(7,748)	(1,440)
Depreciation, amortization and accretion	2,109	1,217	3,121	2,279
Capital expenditures including software costs	1,394	2,165	3,317	3,835
Operating segments | Restaurant/Retail
Information as to the Company's segments [Abstract]
Revenue	28,262	34,827	57,822	74,347
Operating loss	(4,615)	(2,800)	(7,597)	(3,408)
Depreciation, amortization and accretion	1,201	1,057	2,069	1,965
Capital expenditures including software costs	778	1,126	1,841	2,265
Operating segments | Government
Information as to the Company's segments [Abstract]
Revenue	15,985	17,744	31,107	33,885
Operating loss	1,518	2,012	2,881	3,278
Depreciation, amortization and accretion	18	6	37	11
Capital expenditures including software costs	0	37	176	37
Other
Information as to the Company's segments [Abstract]
Operating loss	(356)	(336)	(838)	(856)
Depreciation, amortization and accretion	890	154	1,015	303
Capital expenditures including software costs	616	1,002	1,300	1,533
Reportable geographical components | United States
Information as to the Company's segments [Abstract]
Revenue	41,657	48,845	83,582	101,523
Reportable geographical components | Other Countries
Information as to the Company's segments [Abstract]
Revenue	$ 2,590	$ 3,726	$ 5,347	$ 6,709