Income Taxes (Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property And Equipment [Member]
Deferred tax (liabilities) - current	$ (2,786)	$ (2,609)
U.S. Federal And State [Member]
Deferred tax assets - current	929	5,934
Valuation allowance	0	(5,717)
Net deferred tax assets - current	929	217
Net deferred tax (liabilities) - current	(143)	(217)
Long-term deferred tax asset (liability)	786	0
U.S. Federal And State [Member] | Prepaid Expenses [Member]
Deferred tax (liabilities) - current	(143)	(217)
U.S. Federal And State [Member] | Amortization Of Goodwill For Tax [Member]
Deferred tax assets - current	175	316
U.S. Federal And State [Member] | Amortization Of Startup Costs [Member]
Deferred tax assets - current	98	190
U.S. Federal And State [Member] | Property And Equipment [Member]
Deferred tax assets - current	433	593
U.S. Federal And State [Member] | NOL Carryforward [Member]
Deferred tax assets - current	51	4,167
U.S. Federal And State [Member] | Accrued Liabilities And Other [Member]
Deferred tax assets - current	172	668
Foreign [Member]
Deferred tax assets - current	5,576	5,967
Valuation allowance	0	0
Net deferred tax assets - current	5,576	5,967
Net deferred tax (liabilities) - current	(4,840)	(4,262)
Long-term deferred tax asset (liability)	736	1,705
Foreign [Member] | Property And Equipment [Member]
Deferred tax assets - current	675	715
Foreign [Member] | NOL Carryforward [Member]
Deferred tax assets - current	2,745	2,806
Foreign [Member] | Tax Credits [Member]
Deferred tax assets - current	0	0
Foreign [Member] | Accrued Liabilities And Other [Member]
Deferred tax assets - current	1,046	943
Foreign [Member] | Contingent Liability [Member]
Deferred tax assets - current	348	684
Foreign [Member] | Exchange Rate Gain Or (Loss) [Member]
Deferred tax assets - current	762	819
Net deferred tax (liabilities) - current	(95)	(10)
Foreign [Member] | Intangibles [Member]
Net deferred tax (liabilities) - current	(1,317)	(1,229)
Foreign [Member] | Others [Member]
Net deferred tax (liabilities) - current	$ (642)	$ (414)