Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	45,409,272	45,040,249
Common stock, shares outstanding	33,117,140	33,445,394
Treasury stock, at cost, shares	12,292,132	11,594,815