Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current Assets:
Allowance for doubtful accounts	$ 8,599	$ 9,322
Class A Non-Voting
Shareholders' Investment:
Par or stated value per share (USD per share)	$ 1	$ 1
Shares authorized (shares)	50,000	50,000
Shares issued (shares)	29,525	28,764
Shares outstanding (shares)	29,525	28,764
Class B Voting
Shareholders' Investment:
Par or stated value per share (USD per share)	$ 1	$ 1
Shares authorized (shares)	50,000	50,000
Shares issued (shares)	19,555	19,848
Shares outstanding (shares)	19,555	19,848

Amount of allowance for credit loss on accounts receivable, classified as current.

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