Funds Held for Customers - Summary of Fair Value of Funds Held For Customers (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020
Funds Held For Customers [Line Items]
Amortized cost	$ 678,895	$ 626,740
Gross unrealized gains	958	2,055
Gross unrealized losses	(18)	(11)
Fair value	679,835	628,784
Certificates of Deposit
Funds Held For Customers [Line Items]
Amortized cost	163,733	85,841
Gross unrealized gains	88	115
Gross unrealized losses	(2)	(3)
Fair value	163,819	85,953
Municipal Bonds
Funds Held For Customers [Line Items]
Amortized cost	6,066
Gross unrealized losses	(2)
Fair value	6,064
Corporate Bonds
Funds Held For Customers [Line Items]
Amortized cost	488,317	491,950
Gross unrealized gains	862	1,936
Gross unrealized losses	(14)	(7)
Fair value	489,165	493,879
U.S. Treasury Securities
Funds Held For Customers [Line Items]
Amortized cost	20,779	48,949
Gross unrealized gains	8	4
Gross unrealized losses		(1)
Fair value	$ 20,787	$ 48,952