Earnings/ (Loss) Per Common Share (Details) - shares
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Number of Common Shares        
Shares with anti-dilutive effect, not included in calculation of earnings per share 861,158 701,482 834,394 663,397
Convertible Preferred Stock        
Shares with anti-dilutive effect, not included in calculation of earnings per share 349,900 349,900 349,900 349,900