CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Preferred shares, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred shares, shares authorized (in shares)	5,000,000	5,000,000
Common stock, par value (in dollars per share)	$ 1.00	$ 1.00
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	72,426,139	72,426,139
Common stock, shares, outstanding (in shares)	58,127,948	59,002,205
Treasury stock, shares (in shares)	14,298,191	13,423,934