Consolidated Balance Sheet (Parentheticals) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred stock, authorized	10,000,000	10,000,000
Preferred stock, par value (in dollars per share)	$ 0.10	$ 0.10
Preferred stock, issued	0	0
Common stock, shares authorized	100,000,000	100,000,000
Common stock,par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, outstanding	29,955,000	29,413,000