Quarterly report pursuant to Section 13 or 15(d)

Income Per Share of Common Stock (Details)

v3.7.0.1
Income Per Share of Common Stock (Details) - shares
Jun. 30, 2017
Dec. 31, 2016
Jun. 30, 2016
Earnings Per Share [Abstract]      
Shares of treasury stock excluded from weighted average number of common stock shares outstanding 2,362,418 2,362,418 2,362,418