Equity and Noncontrolling Interest - Reclassifications (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Accumulated Other Comprehensive Loss, Balance at Beginning of Period	$ (65,100)	$ (87,407)
Other Comprehensive Income (Loss) Before Reclassifications	5,624	5,252
Amounts Reclassified from AOCI	611	490
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	6,235	5,742
Related Tax Amounts	127	(296)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	6,362	5,446
Accumulated Other Comprehensive Loss, Balance at End of Period	(58,738)	(81,961)
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Loss, Balance at Beginning of Period	(31,893)	(52,255)
Other Comprehensive Income (Loss) Before Reclassifications	6,764	4,928
Amounts Reclassified from AOCI	0	0
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	6,764	4,928
Related Tax Amounts	0	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	6,764	4,928
Accumulated Other Comprehensive Loss, Balance at End of Period	(25,129)	(47,327)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Loss, Balance at Beginning of Period	(34,093)	(36,168)
Other Comprehensive Income (Loss) Before Reclassifications	(697)	(341)
Amounts Reclassified from AOCI	783	850
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	86	509
Related Tax Amounts	(2)	(191)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	84	318
Accumulated Other Comprehensive Loss, Balance at End of Period	(34,009)	(35,850)
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Loss, Balance at Beginning of Period	886	1,016
Other Comprehensive Income (Loss) Before Reclassifications	(443)	665
Amounts Reclassified from AOCI	(172)	(360)
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	(615)	305
Related Tax Amounts	129	(105)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(486)	200
Accumulated Other Comprehensive Loss, Balance at End of Period	$ 400	$ 1,216