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Common Stock and Treasury Stock (Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025 USD ($) director shares	Sep. 30, 2024 shares	Sep. 30, 2025 USD ($) Vote director shares	Sep. 30, 2024 shares
Common Stock
Number of board of directors | director	8		8
Class A Common Stock
Common Stock
Number of votes per share of common stock | Vote			1
Percentage of directors to be elected			25.00%
Class A Common Stock | Former Shareholder
Common Stock
Conversion of shares			1
Class A Common Stock | Buy-Back Program
Common Stock
Share repurchase program, authorized amount | $	$ 75.8		$ 75.8
Stock repurchase program, remaining authorization amount | $	$ 17.7		$ 17.7
Stock repurchased during period shares	0	0	0	0
Class B Common Stock
Common Stock
Number of votes per share of common stock | Vote			10
Class B Common Stock | Former Shareholder
Common Stock
Common stock, shares issued (in shares)	0		0
Common stock, shares outstanding (in shares)	0		0

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Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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