Quarterly report pursuant to Section 13 or 15(d)

Earnings per share (Details Textual)

v3.7.0.1
Earnings per share (Details Textual) - shares
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 540,001 1,701,927 685,001 1,701,927