Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	100,000	100,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	112,500,000	112,500,000
Common stock, shares issued (in shares)	31,226,336	23,395,211
Common stock, shares outstanding (in shares)	31,221,657	23,319,287
Treasury stock, shares (in shares)	4,679	75,924