Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income ("AOCI") by Component, Net of Tax (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 1,133,209	$ 1,024,311	$ 900,563
Other comprehensive income (loss) before reclassifications	(65,564)	(20,626)	9,795
Amounts reclassified from AOCI	2,402	185	203
Net current-period other comprehensive income	(63,162)	(20,441)	9,998
Ending Balance	2,076,803	1,133,209	1,024,311
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(15,627)	(1,308)	(8,460)
Other comprehensive income (loss) before reclassifications	(15,969)	(14,319)	7,152
Amounts reclassified from AOCI	0	0	0
Net current-period other comprehensive income	(15,969)	(14,319)	7,152
Ending Balance	(31,596)	(15,627)	(1,308)
Interest Rate Swap
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	0	0	0
Other comprehensive income (loss) before reclassifications	(46,067)	0	0
Amounts reclassified from AOCI	1,982	0	0
Net current-period other comprehensive income	(44,085)	0	0
Ending Balance	(44,085)	0	0
Defined Benefit Pension Plan
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(8,594)	(2,472)	(5,318)
Other comprehensive income (loss) before reclassifications	(3,528)	(6,307)	2,643
Amounts reclassified from AOCI	420	185	203
Net current-period other comprehensive income	(3,108)	(6,122)	2,846
Ending Balance	(11,702)	(8,594)	(2,472)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(24,221)	(3,780)	(13,778)
Ending Balance	$ (87,383)	$ (24,221)	$ (3,780)