Earnings Per Share - Additional Information (Details) - shares		3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 21, 2016	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Earnings Per Share [Abstract]
Shares held back in merger to secure indemnification (as a percent)	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)				16,790,576		1,682,110