Income Taxes - Changes in Valuation Allowance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Deferred Tax Assets, Changes in Valuation Allowance
Balance at Beginning of Period	$ (82,833)	$ (90,663)
Change in income tax provision	(2,257)	622
Other change	499	1,119
Foreign currency translation	88	6,089
Balance at End of Period	(84,503)	(82,833)
Federal / State NOLs
Deferred Tax Assets, Changes in Valuation Allowance
Balance at Beginning of Period	(29,304)	(31,399)
Change in income tax provision	(456)	(1,464)
Other change	1,095	(348)
Foreign currency translation	52	3,907
Balance at End of Period	(28,613)	(29,304)
Net Deferred Tax Assets
Deferred Tax Assets, Changes in Valuation Allowance
Balance at Beginning of Period	(52,815)	(58,518)
Change in income tax provision	(1,946)	2,086
Other change	(690)	1,495
Foreign currency translation	68	2,122
Balance at End of Period	(55,383)	(52,815)
Other
Deferred Tax Assets, Changes in Valuation Allowance
Balance at Beginning of Period	(714)	(746)
Change in income tax provision	145	0
Other change	94	(28)
Foreign currency translation	(32)	60
Balance at End of Period	$ (507)	$ (714)