Note 7 - Intangible Assets, Net (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Finite-Lived Intangible Assets [Table Text Block]

	As of December 31,
	2020			2021
	(in thousands)
Customer contracts	$	16,022		$	16,022
Accumulated amortization of intangible assets		(8,491	)		(10,934	)
Intangible assets, net	$	7,531		$	5,088

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

For year ending:
December 31, 2022	$	4,033
December 31, 2023		387
December 31, 2024		387
December 31, 2025		281
December 31, 2026		-
Thereafter		-
Total estimated aggregate amortization expense	$	5,088