Equity-Based Compensation - Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Options outstanding, Beginning balance	1,000,946	694,743
Options granted	233,000	503,850
Options exercised	(62,617)	(57,397)
Options cancelled	(158,126)	(140,250)
Options outstanding, Ending balance	1,013,203	1,000,946	694,743
Options outstanding, Weighted Average Exercise Price, Beginning balance	$ 49.42	$ 42.87
Options exercisable, Ending balance	423,995	288,959
Options granted, Weighted Average Exercise Price	$ 42.99	$ 57.98
Options exercised, Weighted Average Exercise Price	40.17	31.92
Options cancelled, Weighted Average Exercise Price	55.14	57.13
Options outstanding, Weighted Average Exercise Price, Ending balance	$ 48.23	$ 49.42	$ 42.87
Options outstanding, Aggregate Intrinsic Value, Beginning balance	$ 8,166	$ 20,717
Options exercisable, Weighted Average Exercise Price, Ending balance	$ 48.29	$ 42.81
Options granted, Aggregate Intrinsic Value	$ 105	$ 297
Options granted, Weighted Average Remaining Contractual Term	9 years 8 months 26 days	9 years 3 months 11 days
Options exercised, Aggregate Intrinsic Value	$ 1,172	$ 1,530
Options outstanding, Weighted Average Remaining Contractual Term	7 years 10 months 6 days	7 years 9 months 18 days	7 years 8 months 12 days
Options cancelled, Aggregate Intrinsic Value	$ 0	$ 0
Options exercisable, Weighted Average Remaining Contractual Term, Ending balance	6 years 5 months 1 day	6 years 2 months 19 days
Options outstanding, Aggregate Intrinsic Value, Ending balance	$ 4,366	$ 8,166	$ 20,717
Options exercisable, Aggregate Intrinsic Value, Ending balance	$ 4,151	$ 6,111