Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Consolidated Balance Sheets [Abstract]
Securities Held to Maturity, fair value	$ 211,494	$ 201,234
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares outstanding
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	21,499,768	21,220,801
Common stock, shares outstanding	21,499,768	21,220,801
Common stock, unvested restricted stock awards	235,540	219,900
Shares Held in Rabbi Trust	180,058	178,382