MAYO LICENSE AGREEMENT (Details)	1 Months Ended	3 Months Ended						6 Months Ended
	Oct. 31, 2017 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Feb. 28, 2015 USD ($) installment
Other Payments
Charges incurred as part of the research collaboration		$ 30,203,000		$ 14,712,000				$ 62,219,000	$ 29,647,000
Licensing Agreements | Mayo
Other Payments
Charges incurred as part of the research collaboration		1,100,000		1,400,000				2,600,000	2,600,000
Payments for research and development efforts		1,800,000		800,000				2,900,000	2,600,000
Estimated liability for research and development efforts		1,600,000		1,800,000				$ 1,600,000	1,800,000
Amendments
License fees payable in five annual installments										$ 5,000,000.0
License fee payments			$ 1,000,000.0		$ 1,000,000.0	$ 1,000,000.0	$ 1,000,000.0
Number of annual installments in which license fees are payable | installment										5
Number of periods each installment is amortized over								12 months
Amortization of installments		$ 300,000		$ 500,000				$ 300,000	$ 500,000
Licensing Agreements | Mayo | Sales Milestone Range One
Warrants
Amount agreed to be paid upon reaching the specified amount of net sales	$ 200,000
Net sales of a licensed product	5,000,000.0
Licensing Agreements | Mayo | Sales Milestone Range Two
Warrants
Amount agreed to be paid upon reaching the specified amount of net sales	800,000
Net sales of a licensed product	20,000,000.0
Licensing Agreements | Mayo | Sales Milestone Range Three
Warrants
Amount agreed to be paid upon reaching the specified amount of net sales	2,000,000.0
Net sales of a licensed product	$ 50,000,000.0
Licensing Agreements | Mayo | Minimum
Warrants
Royalty payments								$ 25,000