Accumulated Other Comprehensive Income (Loss) by Component (Changes in Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	$ (1,377)	$ 17,433	$ 3,128	$ 12,793
OCI before reclassifications	6,970	(7,482)	1,917	(2,780)
Amount reclassified from accumulated OCI	(945)	(180)	(397)	(242)
Other Comprehensive Income (Loss)	6,025	(7,662)	1,520	(3,022)
Ending Balance	4,648	9,771	4,648	9,771
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	10,562	19,691	8,898	12,244
OCI before reclassifications	5,893	(6,569)	7,557	878
Amount reclassified from accumulated OCI	0	0	0	0
Other Comprehensive Income (Loss)	5,893	(6,569)	7,557	878
Ending Balance	16,455	13,122	16,455	13,122
Accumulated Long-Term Notes Adjustment [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(8,349)	317	(2,491)	2,662
OCI before reclassifications	(784)	(2,517)	(6,642)	(4,862)
Amount reclassified from accumulated OCI	0	0	0	0
Other Comprehensive Income (Loss)	(784)	(2,517)	(6,642)	(4,862)
Ending Balance	(9,133)	(2,200)	(9,133)	(2,200)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(3,468)	(2,677)	(3,299)	(2,703)
OCI before reclassifications	439	(277)	(159)	(418)
Amount reclassified from accumulated OCI	(439)	176	(10)	343
Other Comprehensive Income (Loss)	0	(101)	(169)	(75)
Ending Balance	(3,468)	(2,778)	(3,468)	(2,778)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(122)	102	20	590
OCI before reclassifications	1,422	1,881	1,161	1,622
Amount reclassified from accumulated OCI	(506)	(356)	(387)	(585)
Other Comprehensive Income (Loss)	916	1,525	774	1,037
Ending Balance	$ 794	$ 1,627	$ 794	$ 1,627