Restructuring and other related costs - Restructuring related liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Restructuring Reserve [Roll Forward]
Costs incurred	$ 0	$ (1,792)
Employee severance and related expenses
Restructuring Reserve [Roll Forward]
Beginning balance		96
Costs incurred		(22)
Cash disbursements		(74)
Other adjustments		0
Ending balance		0
Other costs
Restructuring Reserve [Roll Forward]
Beginning balance		675
Costs incurred		867
Cash disbursements		(1,093)
Other adjustments		(131)
Ending balance		318
Employee severance and related expenses and other costs
Restructuring Reserve [Roll Forward]
Beginning balance		771
Costs incurred		845
Cash disbursements		(1,167)
Other adjustments		(131)
Ending balance		$ 318