Consolidated Statements of Stockholders' Equity (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Common Class A [Member]
Dividends declared (in dollars per share)	$ 0.06	$ 0.06
Common Class B [Member]
Dividends declared (in dollars per share)	$ 0.07	$ 0.07
Foreign currency translation adjustment, tax expense	$ 9	$ 51
Unrealized holding losses on marketable securities arising during the period, tax	0	(85)
Change in unfunded SERP liability, tax	$ (422)	$ 954

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

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