Summary of Significant Accounting Policies - Additional Information (Details)				12 Months Ended
	Jun. 30, 2015 USD ($)	Jul. 15, 2014 $ / shares	Dec. 24, 2013 $ / shares shares	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Jan. 01, 2015 Subsidary
Summary Of Significant Accounting Policies [Line Items]
Marketable Securities, Realized Gain (Loss)				$ 0	$ 0	$ 0
Impairments of long-lived assets				0	$ 0	$ 0
Number of subsidiary corporations owned | Subsidary							7
CPRIT | Maximum
Summary Of Significant Accounting Policies [Line Items]
Research grant contract amount	$ 19,800,000			$ 19,800,000
Series A Convertible Preferred Stock
Summary Of Significant Accounting Policies [Line Items]
Number of shares issued for forward sale contract | shares			837,594
Forward sale contract price per share | $ / shares		$ 7.56	$ 5.25
Settlement date of forward sale contract				Jul. 15, 2014