Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Debt securities, available-for-sale, allowance for credit loss, current	$ 112	$ 0
Loans held for sale, fair value	$ 1,001,807	$ 1,656,711
Preferred stock, par or stated value per share (in dollars per share)	$ 1,000	$ 1,000
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par or stated value per share (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	200,000,000	100,000,000
Common stock, shares, issued (in shares)	71,753,705	71,499,829
Treasury stock, shares (in shares)	2,212,224	1,995,996