Consolidated Statements Of Condition (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Held-to-maturity securities, at Fair value	$ 1,198,478	$ 1,036,096	$ 851,842
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000	20,000,000
Common stock, $1.00 stated value (usd per share)	$ 1.00	$ 1.00	$ 1.00
Common stock, 100,000,000 shares authorized (in shares)	100,000,000	100,000,000	100,000,000
Common stock, shares issued (in shares)	56,794,328	56,518,119	56,436,564
Treasury stock, (in shares)	126,482	110,561	107,288
Series D Preferred Stock
Preferred stock, liquidation value per share (usd per share)	$ 25	$ 25	$ 25
Preferred stock, shares outstanding (in shares)	5,000,000	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	5,000,000	5,000,000	5,000,000