Note 1 - Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Deferred Compensation Plan [Table Text Block]

	December 31,
	2021		2020
Deferred compensation plan asset components:
Cash surrender value of corporate-owned life insurance policies	$	21,386	$	19,222
Fair value of mutual funds and money market funds		31,786		26,924
Total	$	53,172	$	46,146
Deferred compensation plan assets reported in:
Other long-term assets	$	53,172	$	46,146
Deferred compensation plan liabilities reported in:
Accrued compensation and related benefits (short-term)	$	282	$	155
Other long-term liabilities		55,489		48,280
Total	$	55,771	$	48,435