Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Mortgage loans held for sale, fair value	$ 318,272	$ 219,848
Preferred stock, par value (usd per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (shares)	5,000,000	5,000,000
Preferred stock, shares issued (shares)	0	0
Preferred stock, shares outstanding (shares)	0	0
Common stock, par value (usd per share)	$ 5	$ 5
Common stock, shares authorized (shares)	150,000,000	150,000,000
Common stock, shares issued (shares)	59,296,725	59,276,725
Common stock, shares outstanding (shares)	56,855,022	58,546,480
Treasury stock (in shares)	2,441,723	750,245