Equity-Based Compensation - Issued and Unvested Shares of Restricted Stock Granted (Detail) - Restricted stock, time vested	Jun. 30, 2017 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares Unvested	2,109,341
Subject to certain market conditions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares Unvested	1,335,700
Subject to certain performance conditions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares Unvested	263,756
Subject to certain service conditions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares Unvested	509,885