Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Common stock, par value (dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	75,000,000	55,000,000
Common stock, shares issued	51,516,309	51,191,184
Common stock, shares outstanding	51,516,309	51,191,184
Preferred shares, par value (dollars per share)	$ 0	$ 0
Preferred shares, shares authorized	5,000,000	5,000,000
Preferred shares, shares issued	0	0
Preferred shares, shares outstanding	0	0