Collaboration with Intrexon and OvaXon Joint Venture (Details) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
Collaboration with Intrexon
Amount of newly issued common stock upon execution of collaborative arrangements		$ 2,500,000
Technology access fee payable in cash upon specified passage of time	2,500,000			2,500,000
Research and development expense	21,784,000	15,802,000	6,323,000
OvaTure Collaboration
Collaboration with Intrexon
Period of commercial milestone payment after the first commercial sale of collaborative arrangement	3 months
Notice period for termination of the agreement by the counterparty	90 days
Minimum period available to counterparty to cure material breach done by other party to avoid termination of agreement	60 days
OvaTure Collaboration | Intrexon
Collaboration with Intrexon
Issuance of common stock shares upon execution of collaborative arrangements (in shares)		273,224
Amount of newly issued common stock upon execution of collaborative arrangements		2,500,000
Technology access fee payable in cash upon specified passage of time	2,500,000			2,500,000
Research and development expense		4,700,000
Research and development expense recorded to additional paid-in capital and common stock	2,500,000
Research and development expense recorded in accrued liabilities		2,200,000
Period of royalty payable depending upon completion of milestone within targeted deadline after transfer of technology	2 years
Maximum | OvaTure Collaboration | Intrexon
Collaboration with Intrexon
Research and development, accreted liability				$ 2,500,000