Consolidated Statements of Stockholders' Equity (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Common Class A [Member]
Dividends declared (in dollars per share)	$ 0.24	$ 0.24
Common Class B [Member]
Dividends declared (in dollars per share)	$ 0.28	$ 0.28
Foreign currency translation adjustment, tax expense	$ (47)	$ (334)
Unrealized losses on interest rate swap cash flow hedge, tax	0	0
Unrealized holding losses on marketable securities arising during the period, tax	0	0
Change in unfunded SERP liability, tax	$ (1,381)	$ (875)

Aggregate dividends declared during the period for each share of common stock outstanding.

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