Summary of Significant Accounting Policies - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2014
Equity Incentive Plan 2011
Significant Accounting Policies [Line Items]
Shares of common stock reserved under EIP	37,000,000
Options outstanding	35,468,800
Stock Plan 2001
Significant Accounting Policies [Line Items]
Number of shares exercisable	12,681,266