Leases - Narrative (Details) $ in Thousands	Sep. 30, 2019 leases	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)
Lessee, Lease, Description [Line Items]
Number of types of leases | leases	2
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 1,937	$ (329)
Retained Earnings [Member]
Lessee, Lease, Description [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 1,900	$ (329)
Lawson [Member]
Lessee, Lease, Description [Line Items]
Lessee's discount rate	5.50%
Bolt [Member]
Lessee, Lease, Description [Line Items]
Lessee's discount rate	4.20%