XML 90 R72.htm IDEA: XBRL DOCUMENT v3.10.0.1
Equity-Based Compensation - Class B Units (Details) - Class B Units - shares
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
May 03, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of units authorized (in shares)         0
Number of units issued in the period (in shares) 0 800,000 0 800,000