Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, shares issued (in shares)	169,760,142	170,501,186
Common stock, shares outstanding (in shares)	165,168,584	166,579,468
Common stock in treasury (in shares)	4,591,558	3,921,718