Segment and Related Information - Reconciliation of Segment Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Identifiable assets by geographic area [Abstract]
Identifiable assets	$ 14,052	$ 14,352
Goodwill by business segment [Abstract]
Goodwill	41,386	41,386
Operating segments | Restaurant/Retail
Identifiable assets by geographic area [Abstract]
Identifiable assets	1,974	1,987
Goodwill by business segment [Abstract]
Goodwill	40,650	40,650
Operating segments | Government
Identifiable assets by geographic area [Abstract]
Identifiable assets	257	272
Goodwill by business segment [Abstract]
Goodwill	736	736
Reportable geographical components | United States
Identifiable assets by geographic area [Abstract]
Identifiable assets	13,760	14,260
Reportable geographical components | Other Countries
Identifiable assets by geographic area [Abstract]
Identifiable assets	292	92
Other
Identifiable assets by geographic area [Abstract]
Identifiable assets	$ 11,821	$ 12,093