Consolidated Balance Sheets (Parentheticals) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Stockholders' equity:
Preferred Stock, No Par Value (in dollars per share)	$ 0	$ 0
Preferred Stock, Shares Authorized (in shares)	10,000,000	10,000,000
Preferred Stock, Shares Issued (in shares)	0	0
Preferred Stock, Shares Outstanding (in shares)	0	0
Common Stock, Par Value (in dollars per share)	$ 1.00	$ 1.00
Common Stock, Shares Authorized (in shares)	20,000,000	20,000,000
Common Stock, Shares, Issued (in shares)	9,498,783	9,498,783
Common Stock, Shares, Outstanding (in shares)	9,498,783	9,498,783