CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - Common Stock [Member] - $ / shares	Mar. 31, 2025	Mar. 31, 2024	Dec. 09, 2015
Common Shares Class A Non-Voting [Member]
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	15,000,000	15,000,000
Common Stock Shares Issued (in shares)	9,450,519	9,435,785
Shares available for purchase through retirement plans (in shares)	200,000
Shares authorized for issuance of grants under equity compensation plan (in shares)			331,500
Common Shares Class B Voting [Member]
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	1,040,000	1,040,000
Common Stock Shares Issued (in shares)	881,452	881,452