Accumulated Other Comprehensive Income (Loss) (Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		$ (2,700)	[1]	$ (12,468)	[1]	$ (20,939)
Other comprehensive income before reclassifications		(3,173)	[1]	10,115	[1]	8,818
Amounts reclassified from accumulated other comprehensive loss		(514)	[1]	(347)	[1]	(347)
Other comprehensive income (loss)		(3,687)	[1]	9,768	[1]	8,471
Ending balance	[1]	(6,387)		(2,700)		(12,468)
Losses on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		0	[1]	0		(111)
Other comprehensive income before reclassifications		(284)	[1]			111
Amounts reclassified from accumulated other comprehensive loss		158	[1]			0
Other comprehensive income (loss)		(126)	[1]			111
Ending balance		(126)	[1]	0	[1]	0
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		(7,716)	[1]	(11,002)	[1]	(12,041)
Other comprehensive income before reclassifications		(3,834)	[1]	3,286	[1]	1,039
Amounts reclassified from accumulated other comprehensive loss		0	[1]	0
Other comprehensive income (loss)		(3,834)	[1]	3,286	[1]	1,039
Ending balance	[1]	(11,550)		(7,716)		(11,002)
Investment in Convertible Preferred Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		344	[1]	0	[1]	126
Other comprehensive income before reclassifications		(86)	[1]	344	[1]	0
Amounts reclassified from accumulated other comprehensive loss		0	[1]	0	[1]	(126)
Other comprehensive income (loss)		(86)	[1]	344	[1]	(126)
Ending balance	[1]	258		344		0
Defined Benefit Plan Items
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		4,672	[1]	(1,466)	[1]	(8,913)
Other comprehensive income before reclassifications		1,031	[1]	6,485	[1]	7,668
Amounts reclassified from accumulated other comprehensive loss		(672)	[1]	(347)	[1]	(221)
Other comprehensive income (loss)		359	[1]	6,138	[1]	7,447
Ending balance	[1]	$ 5,031		$ 4,672		$ (1,466)

[1] All amounts are net of tax. Amounts in parentheses indicate debits