Revenue - Schedule of Disaggregation of Revenue (Major Source) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Total net revenues	$ 16,453	$ 19,559	$ 46,458	$ 56,885
Screen System Sales [Member]
Total net revenues	5,005		13,240
Digital Equipment Sales [Member]
Total net revenues	2,720		8,970
Field Maintenance and Monitoring Services [Member]
Total net revenues	4,209		13,860
Installation Services [Member]
Total net revenues	1,781		4,477
Extended Warranty Sales [Member]
Total net revenues	213		804
Advertising [Member]
Total net revenues	1,480		1,948
Other [Member]
Total net revenues	1,045		3,159
Cinema [Member]
Total net revenues	11,560		33,438
Cinema [Member] | Screen System Sales [Member]
Total net revenues	5,005		13,240
Cinema [Member] | Digital Equipment Sales [Member]
Total net revenues	2,134		7,228
Cinema [Member] | Field Maintenance and Monitoring Services [Member]
Total net revenues	2,966		9,011
Cinema [Member] | Installation Services [Member]
Total net revenues	712		1,420
Cinema [Member] | Extended Warranty Sales [Member]
Total net revenues	213		804
Cinema [Member] | Advertising [Member]
Total net revenues
Cinema [Member] | Other [Member]
Total net revenues	530		1,735
Digital Media [Member]
Total net revenues	5,050		13,593
Digital Media [Member] | Screen System Sales [Member]
Total net revenues
Digital Media [Member] | Digital Equipment Sales [Member]
Total net revenues	630		2,020
Digital Media [Member] | Field Maintenance and Monitoring Services [Member]
Total net revenues	1,372		5,193
Digital Media [Member] | Installation Services [Member]
Total net revenues	1,069		3,057
Digital Media [Member] | Extended Warranty Sales [Member]
Total net revenues
Digital Media [Member] | Advertising [Member]
Total net revenues	1,480		1,948
Digital Media [Member] | Other [Member]
Total net revenues	499		1,375
Other [Member]
Total net revenues	16		49
Other [Member] | Screen System Sales [Member]
Total net revenues
Other [Member] | Digital Equipment Sales [Member]
Total net revenues
Other [Member] | Field Maintenance and Monitoring Services [Member]
Total net revenues
Other [Member] | Installation Services [Member]
Total net revenues
Other [Member] | Extended Warranty Sales [Member]
Total net revenues
Other [Member] | Advertising [Member]
Total net revenues
Other [Member] | Other Revenue [Member]
Total net revenues	16		49
Eliminations [Member]
Total net revenues	(173)		(622)
Eliminations [Member] | Screen System Sales [Member]
Total net revenues
Eliminations [Member] | Digital Equipment Sales [Member]
Total net revenues	(44)		(278)
Eliminations [Member] | Field Maintenance and Monitoring Services [Member]
Total net revenues	(129)		(344)
Eliminations [Member] | Installation Services [Member]
Total net revenues
Eliminations [Member] | Extended Warranty Sales [Member]
Total net revenues
Eliminations [Member] | Advertising [Member]
Total net revenues
Eliminations [Member] | Other [Member]
Total net revenues