CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2018	Dec. 31, 2017
CONSOLIDATED BALANCE SHEETS
Preferred stock, par value (in dollars per share)	$ 0.01
Preferred stock, shares authorized	10,000,000
Preferred stock, shares issued	0
Common stock, par value (in dollars per share)	$ 0.01
Common stock, shares authorized	30,000,000
Common stock, shares issued	19,096,300	19,096,300
Common stock, shares outstanding	17,792,384	17,759,446
Treasury stock, shares	1,303,916	1,336,854