Summary of Significant Accounting Policies - Impact on Cash Flow Statement (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Cash Flows
Net income	$ 64,455	$ 53,823	$ 38,598
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred income tax expense (benefit)	2,754	4,134	(21,870)
Changes in operating assets and liabilities:
Deferred contract costs	(54,944)	(34,992)
Prepaid expenses and other	(196)	389	(2,141)
Accrued expenses		13,625
Net cash provided by operating activities	$ 112,655	115,032	$ 97,866
Impact from Adoption | Topic 606
Cash Flows
Net income		29,086
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred income tax expense (benefit)		10,187
Changes in operating assets and liabilities:
Deferred contract costs		(34,992)
Prepaid expenses and other		1,730
Accrued expenses		(6,011)
Balances under ASC 605
Cash Flows
Net income		24,737
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred income tax expense (benefit)		(6,053)
Changes in operating assets and liabilities:
Prepaid expenses and other		(1,341)
Accrued expenses		19,636
Net cash provided by operating activities		$ 115,032