Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Investment Securities:
Available-for-sale Securities Pledged as Collateral	$ 465,491	$ 467,143
Stockholders' Equity:
Preferred stock, par value	$ 1.00	$ 1.00
Preferred stock, shares authorized	2,000,000	2,000,000
Preferred stock, shares issued	6,000	6,000
Common stock, par value	$ 5.00	$ 5.00
Common Stock, Shares Authorized	120,000,000	120,000,000
Common stock, shares issued	96,830,977	96,830,977
Treasury stock, shares	3,362,811	367,487