Segment and Related Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) h segment	Mar. 31, 2018 USD ($)
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	$ 44,682	$ 55,661
Operating (loss) income	(2,101)	138
Other (expense) income, net	(430)	49
Interest expense, net	(146)	(41)
(Loss) income before provision for income taxes	(2,677)	146
Depreciation, amortization and accretion	1,012	1,062
Capital expenditures including software costs	1,923	1,670
Operating segments \| Restaurant/Retail
Information as to the Company's segments [Abstract]
Revenue	29,560	39,520
Operating (loss) income	(2,982)	(608)
Depreciation, amortization and accretion	868	908
Capital expenditures including software costs	1,063	1,139
Operating segments \| Government
Information as to the Company's segments [Abstract]
Revenue	15,122	16,141
Operating (loss) income	1,363	1,266
Depreciation, amortization and accretion	19	5
Capital expenditures including software costs	176	0
Other
Information as to the Company's segments [Abstract]
Operating (loss) income	(482)	(520)
Depreciation, amortization and accretion	125	149
Capital expenditures including software costs	684	531
Reportable geographical components \| United States
Information as to the Company's segments [Abstract]
Revenue	41,925	52,678
Reportable geographical components \| Other Countries
Information as to the Company's segments [Abstract]
Revenue	$ 2,757	$ 2,983

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