Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Current Assets:
Allowance for doubtful accounts	$ 8,145	$ 8,599
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)	30,124	29,525
Shares outstanding (shares)	30,124	29,525
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)	19,145	19,555
Shares outstanding (shares)	19,145	19,555

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

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