Summary of Significant Accounting Policies - Intangibles and Goodwill (Details) $ in Thousands				1 Months Ended	12 Months Ended
	Oct. 02, 2017 USD ($)	Dec. 27, 2016 USD ($)	Jul. 31, 2014 USD ($)	Jan. 31, 2018 USD ($)	Jun. 30, 2019 USD ($) item	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)
Intangible Assets:
Amortization expense					$ 3,000	$ 3,000		$ 2,900
Number of reporting units | item					1
Future amortization of intangible assets
2020						2,900
2021						2,400
2022						2,200
2023						2,000
2024						1,400
Thereafter						3,800
Rollforward of Goodwill
Balance at the beginning of the period					$ 90,197	87,200	$ 87,300
Acquisition						2,983
Balance at the end of the period					90,197	90,197	87,200	$ 87,300
Intangible Assets
Gross Carrying Amount					42,700	42,700
Accumulated Amortization					(27,700)	(24,700)
Net Carrying Value					15,000	18,000
Middlebury Interactive Languages LLC
Intangible Assets:
Ownership percentage acquired (as a percent)		40.00%
Cash purchase price		$ 9,100
Trade names
Intangible Assets
Gross Carrying Amount					17,600	17,600
Accumulated Amortization					(9,400)	(8,500)
Net Carrying Value					8,200	9,100
Customer and distributor relationships
Intangible Assets
Gross Carrying Amount					20,500	20,500
Accumulated Amortization					(14,700)	(13,400)
Net Carrying Value					5,800	7,100
Developed technology
Intangible Assets
Gross Carrying Amount					3,200	3,200
Accumulated Amortization					(2,800)	(2,200)
Net Carrying Value					400	1,000
Other
Intangible Assets
Gross Carrying Amount					1,400	1,400
Accumulated Amortization					(800)	(600)
Net Carrying Value					$ 600	800
LearnBop
Intangible Assets:
Ownership percentage acquired (as a percent)			51.00%	49.00%
Cash purchase price			$ 6,500	$ 500
LTS
Rollforward of Goodwill
Acquisition							$ 100
Adjustments						$ 3,000
Big Universe Inc.
Intangible Assets:
Ownership percentage acquired (as a percent)	100.00%
Cash and contingent consideration paid	$ 3,300