Note K - Notes Payable and Long-term Debt - Schedule of Notes Payable and Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	$ 49,985	$ 84,124
Less debt issuance costs, net	62	207
Grand total	49,923	83,917
Less current portion	33,371	23,589
Non-current portion	16,552	60,328
Bank acceptance notes issued to vendors with a zero percent interest rate	6,310	4,628
Chailease Finance Co, Ltd. [Member] | Promissory Note [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	4,262	6,331
Chailease Finance Co, Ltd. [Member] | Promissory Note 2 [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	4,633	0
Branch Banking and Trust Company [Member] | Term Loan [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	0	20,067
Branch Banking and Trust Company [Member] | CapEx Loan [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	0	19,164
Revolving Credit Facility [Member] | Branch Banking and Trust Company [Member] | Third Amendment to Loan Agreement with BB and T [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	20,000	23,104
Revolving Credit Facility [Member] | Taishin International Bank [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021		3,256
Revolving Credit Facility [Member] | Taishin International Bank [Member] | Credit Facility [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	3,336	0
Revolving Credit Facility [Member] | Development Bank of Singapore (Taiwan) Ltd. [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	0	3,550
Revolving Credit Facility [Member] | Far Eastern [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	2,668	0
Revolving Credit Facility [Member] | China Construction Bank Co., Ltd. [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	0	8,652
Revolving Credit Facility [Member] | SPD Bank [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	7,919	0
Revolving Credit Facility [Member] | China Zheshang Bank Co., Ltd [Member]
Revolving line of credit with a U.S. bank up to $20,000 (2019) and $60,000 (2018) with interest at LIBOR plus 1.5% (2019) and 1.4% (2018), maturing April 2, 2021	$ 7,167	$ 0