Stock Compensaton - Stock Option Activity (Detail)	6 Months Ended
	Jun. 30, 2016 $ / shares shares
Number of Shares
Options outstanding, beginning balance (in shares) | shares	10,232,969
Granted (in shares) | shares	4,490,700
Forfeited (in shares) | shares	(1,928,884)
Exercised (in shares) | shares	(540,619)
Options outstanding, ending balance (in shares) | shares	12,254,166
Weighted Average Exercise Price Per Share
Options outstanding, beginning balance (in dollars per share) | $ / shares	$ 10.00
Granted (in dollars per share) | $ / shares	6.30
Forfeited (in dollars per share) | $ / shares	8.71
Exercised (in dollars per share) | $ / shares	4.95
Options outstanding, ending balance (in dollars per share) | $ / shares	$ 9.07