Employee Benefit Plans - Summary of Company's Stock Option and Restricted Stock Unit Activity (Detail) shares in Thousands	12 Months Ended
	Dec. 31, 2016 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Available for Grant, Beginning balance	6,150
Shares Available for Grant, Authorized	2,000
Number of Shares, Granted, Shares Available for Grant	(6,201)
Number of Shares, Forfeited or Canceled, Options and Other than Options	1,963
Shares Available for Grant, Ending balance	3,912
Stock Options Outstanding [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Beginning balance	5,674
Number of Shares, Authorized	0
Number of Shares, Granted	946
Number of Shares, Options exercised	(150)
Number of Shares, Forfeited or cancelled	(1,451)
Number of Shares, Ending balance	5,019
Weighted Average Exercise Price, Beginning balance | $ / shares	$ 6.56
Weighted Average Exercise Price, Granted | $ / shares	3.19
Weighted Average Exercise Price, Options exercised | $ / shares	4.77
Weighted Average Exercise Price, Forfeited or cancelled | $ / shares	6.46
Weighted Average Exercise Price, Ending balance | $ / shares	$ 6.01
Restricted Stock Units Outstanding [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Authorized	0
Number of Units, Beginning balance	2,182
Number of Units, Granted	3,503
Number of Units, Exercised	0
Number of Units, Shares released	(1,480)
Number of Units, Forfeited or cancelled	(341)
Number of Units, Ending balance	3,864
Weighted Average Grant Date Fair Value, Beginning balance | $ / shares	$ 6.99
Weighted Average Grant Date Fair Value, Granted | $ / shares	3.78
Weighted Average Grant Date Fair Value, Shares released | $ / shares	6.57
Weighted Average Grant Date Fair Value, Forfeited or cancelled | $ / shares	5.56
Weighted Average Grant Date Fair Value, Ending balance | $ / shares	$ 4.26