Leasing - Operating Lease Amounts in Statement of Condition (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Leases [Abstract]
ROU assets	$ 33,231	$ 33,501
Current lease liabilities	3,188	3,256
Non-current lease liabilities	32,450	32,666
Total lease liabilities	$ 35,638	$ 35,922