Charges Related To Restructuring Activities (Details) - USD ($)	3 Months Ended				9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 1,582,000	$ 1,149,000	$ 1,682,000		$ 1,682,000
Charges	1,628,000	1,321,000	692,000	$ 920,000	3,641,000	$ 1,665,000
Payments	(2,039,000)	(888,000)	(1,225,000)		(4,152,000)	(4,314,000)
Ending Balance	1,171,000	1,582,000	1,149,000		1,171,000
Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	1,582,000	1,122,000	1,657,000		1,657,000
Charges	1,628,000	1,299,000	670,000
Payments	(2,039,000)	(839,000)	(1,205,000)
Ending Balance	1,171,000	1,582,000	1,122,000		1,171,000
Contract Termination
Restructuring Reserve [Roll Forward]
Beginning Balance	0	27,000	25,000		25,000
Charges			22,000
Restructuring Reserve, Accrual Adjustment	0	22,000
Payments	0	(49,000)	(20,000)
Ending Balance	0	0	27,000		0
All Other
Restructuring Reserve [Roll Forward]
Beginning Balance	609,000	327,000	820,000		820,000
Charges	34,000	346,000	(181,000)	10,000	199,000	268,000
Payments	(380,000)	(64,000)	(312,000)
Ending Balance	263,000	609,000	327,000		263,000
All Other | Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	609,000	327,000	820,000		820,000
Charges	34,000	346,000	(181,000)			268,000
Payments	(380,000)	(64,000)	(312,000)
Ending Balance	263,000	609,000	327,000		263,000
All Other | Contract Termination
Restructuring Reserve [Roll Forward]
Beginning Balance	0	0	0		0
Charges	0	0	0
Payments	0	0	0
Ending Balance	0	0	0		0
Europe
Restructuring Reserve [Roll Forward]
Beginning Balance	287,000	276,000	181,000		181,000
Charges	1,263,000			769,000	1,903,000	1,170,000
Payments		(309,000)	(225,000)
Ending Balance		287,000	276,000
Europe | Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	287,000	276,000	181,000		181,000
Charges	1,263,000	320,000	320,000		1,903,000	1,170,000
Payments	(911,000)	(309,000)	(225,000)
Ending Balance	639,000	287,000	276,000		639,000
Europe | Contract Termination
Restructuring Reserve [Roll Forward]
Beginning Balance	0	0	0		0
Charges	0	0	0
Payments	0	0	0
Ending Balance	0	0	0		0
North America
Restructuring Reserve [Roll Forward]
Beginning Balance	686,000	546,000	681,000		681,000
Charges			553,000	$ 141,000	1,539,000	227,000
Restructuring Reserve, Accrual Adjustment	331,000	655,000
Payments	(748,000)	(515,000)	(688,000)
Ending Balance	269,000	686,000	546,000		269,000
North America | Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	686,000	519,000	656,000		656,000
Charges	331,000	633,000	531,000		1,495,000	362,000
Payments	(748,000)	(466,000)	(668,000)
Ending Balance	269,000	686,000	519,000		269,000
North America | Contract Termination
Restructuring Reserve [Roll Forward]
Beginning Balance	0	27,000	25,000		25,000
Charges					44,000	$ (135,000)
Restructuring Reserve, Accrual Adjustment	0	22,000	22,000
Payments	0	(49,000)	(20,000)
Ending Balance	$ 0	$ 0	$ 27,000		$ 0