CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Common stock, par value (in usd per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	51,500,000	51,500,000
Common stock, shares issued (in shares)	27,080,403	24,061,568
Common stock, shares outstanding (in shares)	26,728,242	23,709,407
Subsidiary, Sale of Stock [Line Items]
Treasury stock, common shares (in shares)	352,161	352,161
Subsidiaries
Subsidiary, Sale of Stock [Line Items]
Treasury stock, common shares (in shares)	145,820	145,820