CONDENSED CONSOLIDATED STATEMENTS OF CONDITION (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Investments held-to-maturity, fair value	$ 216,420	$ 222,024
Common stock, par value	$ 1.00	$ 1.00
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	24,954,892	24,905,392
Common stock, shares outstanding	24,954,892	24,905,392