Restructuring Activities (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Restructuring Reserve [Roll Forward]
Restructuring liability, beginning balance	$ 282,000	$ 186,000	$ 391,000	$ 309,000
Amounts expensed	0	58,000	0	119,000
Amounts expensed - discontinued operations	0	396,000	0	396,000
Amounts paid	(94,000)	(88,000)	(203,000)	(272,000)
Restructuring liability, ending balance	$ 188,000	$ 552,000	$ 188,000	$ 552,000