Earnings Per Share - Additional Information (Details) - shares		3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 21, 2016	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Earnings Per Share [Abstract]
Shares held back in merger to secure indemnification	10.00%	10.00%	10.00%	10.00%	10.00%
Period shares will be held back for	24 months
Percentage of shares issued on first anniversary of merger	50.00%
Percentage of shares issued on second anniversary of merger	50.00%
Treasury shares not included in the calculation of earnings per share (in shares)				1,775,561		1,682,110