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v3.25.1

NET INCOME PER COMMON SHARE AND EQUITY PER COMMON SHARE (Details) - $ / shares | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024
Antidilutive Securities Excluded from Computation of Earnings Per Share [Abstract] |  |  |
Shares excluded from calculations of diluted net income per share (in shares) | 0 | 0 |
Shares used in computing basic and diluted net income per share [Abstract] |  |  |
Weighted average common shares outstanding during the period for Basic computation (in shares) | 10,302,000 | 10,287,000 |
Dilutive effect of employee stock options and awards (in shares) | 4,000 | 4,000 |
Weighted average common shares outstanding during the period for Diluted computation (in shares) | 10,306,000 | 10,291,000 |
Earnings Per Share [Abstract] |  |  |
Equity per common share (in dollars per share) | $ 0.53 | $ 0.43 |
Common Stock [Member] | Class A Stock [Member] |  |  |
Common Stock [Abstract] |  |  |
Common stock, shares authorized (in shares) | 15,000,000 | 15,000,000 |
Common stock, shares issued (in shares) | 9,421,542 | 9,406,808 |
Common stock, shares outstanding (in shares) | 9,421,542 | 9,406,808 |
Common stock, par value (in dollars per share) | $ 1 | $ 1 |
Earnings Per Share [Abstract] |  |  |
Equity per common share (in dollars per share) | $ 23.46 |  | $ 23.24
Common Stock [Member] | Class B Stock [Member] |  |  |
Common Stock [Abstract] |  |  |
Common stock, shares authorized (in shares) | 1,040,000 | 1,040,000 |
Common stock, shares issued (in shares) | 881,452 | 881,452 |
Common stock, shares outstanding (in shares) | 881,452 | 881,452 |
Common stock, par value (in dollars per share) | $ 1 | $ 1 |
Restricted Stock [Member] |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Abstract] |  |  |
Shares excluded from calculations of diluted net income per share (in shares) | 0 | 0 |

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- Definition Total number of common shares of an entity that have been sold or granted to shareholders (excludes 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. + References No definition available. + Details
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