COMMITMENTS AND CONTINGENCIES - Licensing Agreements (Details) - USD ($)						1 Months Ended	3 Months Ended								12 Months Ended
	Jul. 24, 2015	Dec. 16, 2014	Apr. 02, 2014	Jun. 21, 2013	Jul. 26, 2010	Aug. 31, 2014	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2009
Commitments and contingencies
Number of shares of common stock covered by warrants																		75,000
Number of shares of restricted stock granted as a consideration for the expanded license	7,000,000	4,000,000	11,500,000	6,300,000
Research and development expense							$ 9,365,000	$ 9,863,000	$ 8,115,000	$ 6,571,000	$ 4,992,000	$ 9,073,000	$ 7,174,000	$ 7,430,000	$ 33,914,000	$ 28,669,000	$ 27,678,000
Licensing Agreements | Hologic
Commitments and contingencies
Milestone payment contingent upon FDA approval						$ 100,000
Licensing Agreements | MDx Health
Commitments and contingencies
Minimum royalty fee that the entity is required to pay on each anniversary					$ 100,000
Amount agreed to be paid upon the first commercial sale of a licensed product					100,000
Licensing Agreements | MDx Health | Sales Milestone Range One
Commitments and contingencies
Amount agreed to be paid upon reaching the specified amount of net sales					150,000
Net sales of a licensed product					10,000,000
Licensing Agreements | MDx Health | Sales Milestone Range Two
Commitments and contingencies
Amount agreed to be paid upon reaching the specified amount of net sales					750,000
Net sales of a licensed product					50,000,000
Licensing Agreements | MDx Health | Sales Milestone Range Three
Commitments and contingencies
Amount agreed to be paid upon reaching the specified amount of net sales					1,000,000
Net sales of a licensed product					$ 50,000,000