Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Condensed Consolidated Balance Sheets [Abstract]
Allowance for doubtful accounts	$ 9.1	$ 9.1
Common stock stated value per share	$ 20.00	$ 20.00
Authorized	50,000,000	50,000,000
Issued to voting trustees	19,401,014	18,956,496
Issued to shareholders	4,004,296	3,929,845
In treasury, at cost	(255,750)	(53,108)
Outstanding Common Stock	23,149,560	22,833,233

Issued to shareholders

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Issued to voting trustees

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- Definition

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

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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