Significant agreements (Details) $ in Thousands |
1 Months Ended | 3 Months Ended | 9 Months Ended | |
|---|---|---|---|---|
|
Jan. 31, 2020
item
|
Dec. 31, 2019
USD ($)
|
Dec. 31, 2019
USD ($)
|
Mar. 31, 2019
USD ($)
|
|
| Significant agreements | ||||
| Prepaid expenses and other current assets | $ 5,220 | $ 5,220 | $ 3,696 | |
| Regeneron Pharmaceuticals, Inc | ||||
| Significant agreements | ||||
| Payments received under the terms of the agreement | 760 | 2,008 | ||
| Prepaid expenses and other current assets | $ 1,017 | $ 1,017 | $ 337 | |
| Bristol-Myers Squibb Company [Member] | ||||
| Significant agreements | ||||
| Number Of Patients | item | 125 |