Condensed Consolidated Statements of Financial Condition (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	3,000,000	3,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	113,914,902	113,914,902
Common stock, shares outstanding (in shares)	96,924,781	98,518,668
Treasury stock, shares (in shares)	16,990,121	15,396,234
Securities held to maturity, fair value	$ 276,988	$ 338,718