CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Common stock, shares authorized	200,000,000	200,000,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares outstanding	64,929,510	68,998,069
Treasury stock, shares	6,638,643	1,987,073