Stock Compensaton - Stock and Stock Unit Activity (Detail) - Stock and stock units	6 Months Ended
	Jun. 30, 2016 $ / shares shares
Number of Shares
Outstanding, beginning balance (in shares) | shares	4,493,054
Granted / awarded (in shares) | shares	3,491,512
Forfeited (in shares) | shares	(2,513,304)
Vested or restrictions lapsed (in shares) | shares	(1,855,022)
Outstanding, ending balance (in shares) | shares	3,616,240
Weighted Average Exercise Price Per Share
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 8.64
Granted / awarded (in dollars per share) | $ / shares	6.57
Forfeited (in dollars per share) | $ / shares	7.64
Vested or restrictions lapsed (in dollars per share) | $ / shares	8.48
Outstanding, ending balance (in dollars per share) | $ / shares	$ 7.42