v3.21.1

Revenues from contracts with customers - Revenues by end market (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 26, 2021	Mar. 27, 2020	Mar. 26, 2021	Mar. 27, 2020
Disaggregation of Revenue [Line Items]
Revenues	$ 479,317	$ 411,210	$ 1,369,783	$ 1,236,723
Revenue from contract with customer benchmark | Geographic concentration risk
Disaggregation of Revenue [Line Items]
Revenues, percentage	100.00%	100.00%	100.00%	100.00%
Optical communications
Disaggregation of Revenue [Line Items]
Revenues	$ 361,739	$ 308,566	$ 1,053,496	$ 933,013
Optical communications | Revenue from contract with customer benchmark | Geographic concentration risk
Disaggregation of Revenue [Line Items]
Revenues, percentage	75.50%	75.00%	76.90%	75.40%
Lasers, sensors and other
Disaggregation of Revenue [Line Items]
Revenues	$ 117,578	$ 102,644	$ 316,287	$ 303,710
Lasers, sensors and other | Revenue from contract with customer benchmark | Geographic concentration risk
Disaggregation of Revenue [Line Items]
Revenues, percentage	24.50%	25.00%	23.10%	24.60%

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