Leases - Component of Lease Cost and Consolidated Balance Sheet Amounts (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Mar. 31, 2019
Leases [Abstract]
Operating lease cost	$ 514	$ 920
Short-term lease cost	50	255
Variable lease cost	71	207
Sublease income	0	0
Total lease cost	635	1,382
Operating leases
Operating lease right-of-use assets	7,154	7,154	$ 0
Operating lease liabilities	$ 7,577	$ 7,577
Weighted-average remaining lease term
Operating leases	15 years 6 months	15 years 6 months
Weighted-average discount rate
Operating leases	4.51%	4.51%