Summary of Significant Accounting Policies - Fair Value Measurements (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 27, 2016	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Middlebury Interactive Languages LLC
Fair value measurements categorized as Level 3 of the valuation hierarchy, valued on a recurring basis
Ownership percentage acquired (as a percent)	40.00%
Cash purchase price	$ 9,100
Significant Unobservable Inputs (Level 3) | Measured on a recurring basis
Fair value measurements categorized as Level 3 of the valuation hierarchy, valued on a recurring basis
Fair Value, beginning of period			$ 2,806	$ 9,748
Purchases, Issuances and Settlements				(9,134)
Unrealized Gains/(Losses)				2,192
Fair Value, end of period				2,806
Significant Unobservable Inputs (Level 3) | Measured on a recurring basis | Middlebury Interactive Languages LLC
Fair value measurements categorized as Level 3 of the valuation hierarchy, valued on a recurring basis
Redeemable noncontrolling interest fair value, beginning balance			6,801
Purchases, Issuances and Settlements				(9,134)
Unrealized Gains/(Losses)				2,333
Redeemable noncontrolling interest fair value, ending balance				6,801
Acquisitions | Measured on a recurring basis
Fair value measurements categorized as Level 3 of the valuation hierarchy, valued on a recurring basis
Contingent consideration, fair value, beginning balance		$ 1,345
Contingent consideration, fair value, ending balance			1,345
Acquisitions | Significant Unobservable Inputs (Level 3) | Measured on a recurring basis
Fair value measurements categorized as Level 3 of the valuation hierarchy, valued on a recurring basis
Contingent consideration, fair value, beginning balance		1,345	2,806	2,947
Purchases, Issuances and Settlements		(1,347)	(1,319)
Unrealized Gains/(Losses)		$ 2	(142)	(141)
Contingent consideration, fair value, ending balance			$ 1,345	$ 2,806