Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2012	Dec. 31, 2011
Condensed Consolidated Balance Sheets [Abstract]
Common Stock, par value	$ 0.01	$ 0.01
Common Stock, shares authorized	90,000,000	90,000,000
Common Stock, shares issued	39,919,972	39,677,291
Treasury Stock at cost, shares	3,247,206	3,201,858