Note 7 - Income Taxes (Details Textual) $ in Thousands, $ in Billions		1 Months Ended
		Dec. 31, 2019 USD ($)	Aug. 31, 2016 USD ($)	Aug. 31, 2016 MXN ($)	Dec. 31, 2018 USD ($)
Undistributed Earnings of Foreign Subsidiaries		$ 0			$ 14,600
Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries					3,000
Deferred Tax Assets, Operating Loss Carryforwards, Total	[1]	11,333			$ 14,143
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax		100
Deferred Tax Assets, Tax Credit Carryforwards, Foreign		9,100
Future Taxable Income Needed to Realize U.S. Deferred Tax Assets		179,200
Income Tax Examination, Penalties and Interest Expense, Total		3,200
Decrease in Unrecognized Tax Benefits is Reasonably Possible		100
Tax Period 2024 to 2038 [Member]
Deferred Tax Assets, Tax Credit Carryforwards, General Business		2,200
Foreign Tax Authority [Member]
Deferred Tax Assets, Operating Loss Carryforwards, Total		$ 42,000
Mexican Tax Authority [Member] | Tax Year 2010 [Member]
Income Tax Examination, Estimate of Possible Loss			$ 157,000	$ 3

[1] At December 31, 2019, non-U.S. operating loss carryforwards of $42.0 million expire between 2021 and 2027.