Income Taxes - Statutory Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes
Statutory tax rate percentage	21.00%	21.00%	35.00%
Reconciliation of statutory tax and provision
Expected tax at statutory rate	$ 3,255	$ 747	$ 2,933
Foreign taxes at other rates	(982)	(1,308)	(3,139)
US tax on foreign earnings, net of foreign tax credits			(226)
Valuation reserves on NOL carryforwards	2,042	2,894	3,997
US tax reform - deemed repatriation		(2,534)	18,472
US tax reform - changes in indefinite reinvestment assertion			7,281
US tax reform - deferred tax expense from tax rate change		(462)	2,339
State income taxes, net of federal benefit	108	(79)	(59)
Uncertain tax positions	1,845
Disallowed expenses and other	438	449	(818)
Total	$ 6,706	$ (293)	$ 30,780