Defined Benefit Pension Plans - Level 3 Plan Asset Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at January 1,	$ 12,834	$ 10,215
Net Realized and Unrealized Gains	(54)	786
Effect of Foreign Currency	(963)	984
Fair value of plan assets at December 31,	11,890	12,834
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at January 1,	12,045	9,432
Net Realized and Unrealized Gains	(35)	780
Net Purchases, Issuances, Settlements, and Other	0	9
Net Transfers Into Level 3	0	833
Effect of Foreign Currency	(907)	991
Fair value of plan assets at December 31,	11,103	12,045
Guaranteed Insurance Contract, Type of Benefit [Domain]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at January 1,	8,384
Fair value of plan assets at December 31,	8,020	8,384
Guaranteed Insurance Contract, Type of Benefit [Domain] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at January 1,	8,384	7,011
Net Realized and Unrealized Gains	(158)	257
Net Purchases, Issuances, Settlements, and Other	141	102
Net Transfers Into Level 3	0	0
Effect of Foreign Currency	(347)	1,014
Fair value of plan assets at December 31,	8,020	8,384
Securities (Assets) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at January 1,	3,661
Fair value of plan assets at December 31,	3,083	3,661
Securities (Assets) [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at January 1,	3,661	2,421
Net Realized and Unrealized Gains	123	523
Net Purchases, Issuances, Settlements, and Other	(141)	(93)
Net Transfers Into Level 3	0	833
Effect of Foreign Currency	(560)	(23)
Fair value of plan assets at December 31,	$ 3,083	$ 3,661