Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	1 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Disclosure Summary Of Significant Accounting Policies Additional Information Detail [Line Items]
Working capital	$ 23,759,175	$ 23,759,175		$ 23,152,970
Certificates of deposit	$ 23,435,936	$ 23,435,936		10,427,810
Expected forfeitures		0.00%	0.00%
Shares authorized but unissued common stock	12,020,536	12,020,536
Tax benefit attributed to the stock-based compensation expense		$ 0
Unrecognized Tax Benefits	$ 0	0
Unrecognized Tax Benefits, liability, Penalties or Interest Accrued	0	$ 0
Shares excluded from the computation of diluted net loss per share		38,890,839	19,495,807
Intellectual Property
Disclosure Summary Of Significant Accounting Policies Additional Information Detail [Line Items]
Fair value of intellectual property				$ 11,000,000
Computer Equipment
Disclosure Summary Of Significant Accounting Policies Additional Information Detail [Line Items]
Estimated useful lives of property and equipment		3 years
Minimum
Disclosure Summary Of Significant Accounting Policies Additional Information Detail [Line Items]
Estimated useful lives of property and equipment		3 years
Maximum
Disclosure Summary Of Significant Accounting Policies Additional Information Detail [Line Items]
Estimated useful lives of property and equipment		5 years
California Institute of Regenerative Medicine
Disclosure Summary Of Significant Accounting Policies Additional Information Detail [Line Items]
Proceeds from funds awarded	$ 19,919,449