Divestiture and Discontinued Operations (Details) - USD ($)			3 Months Ended		6 Months Ended
	May 05, 2017	Nov. 04, 2015	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Operations
Income from discontinued operations, net of taxes			$ 0	$ 0	$ 0	$ 183,000
PAR Springer-Miller Systems, Inc.
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total consideration		$ 16,600,000
Consideration received	$ 4,200,000	$ 12,100,000
Consideration payable period from closing date		18 months
Consideration could be received upon achievement of targets		$ 1,500,000
Consideration could be received upon achievement of targets per year		500,000
Operations
Total revenues			0	0	0	0
Income from discontinued operations before income taxes			0	0	0	284,000
Provision for income taxes			0	0	0	(101,000)
Income from discontinued operations, net of taxes			$ 0	$ 0	$ 0	$ 183,000
PAR Springer-Miller Systems, Inc. | Maximum
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration receivable		$ 4,500,000