Consolidated Statements Of Condition (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Held-to-maturity securities, Fair Value	$ 924,344	$ 878,111	$ 0
Preferred stock, no par value
Preferred stock, 20,000,000 shares authorized	20,000,000	20,000,000	20,000,000
Common stock, no par value
Common stock, $1.00 stated value	$ 1.00	$ 1.00	$ 1.00
Common stock, 100,000,000 shares authorized	100,000,000	100,000,000	100,000,000
Common stock, shares issued	48,608,559	48,468,894	47,474,721
Treasury stock, shares	89,561	85,615	85,113
Series C Preferred Stock
Preferred stock, liquidation value per share	$ 1,000	$ 1,000	$ 1,000
Preferred stock, shares outstanding	126,257	126,287	126,427
Series D Preferred Stock
Preferred stock, liquidation value per share	$ 25	$ 25	$ 0
Preferred stock, shares outstanding	5,000,000	5,000,000	0