Revenues from contracts with customers - Schedule of Revenues by End Market and Product (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 26, 2025	Dec. 27, 2024	Dec. 26, 2025	Dec. 27, 2024
Disaggregation of Revenue [Line Items]
Revenues	$ 1,132,888	$ 833,608	$ 2,111,016	$ 1,637,836
Product concentration risk \| Revenue from contract with customer benchmark
Disaggregation of Revenue [Line Items]
Revenues, percentage	100.00%	100.00%	100.00%	100.00%
Optical communications
Disaggregation of Revenue [Line Items]
Revenues	$ 832,590	$ 647,150	$ 1,579,486	$ 1,273,465
Optical communications \| Product concentration risk \| Revenue from contract with customer benchmark
Disaggregation of Revenue [Line Items]
Revenues, percentage	73.50%	77.60%	74.80%	77.80%
Optical communications \| Telecom
Disaggregation of Revenue [Line Items]
Revenues	$ 412,248	$ 299,101	$ 747,968	$ 627,982
Optical communications \| Datacom
Disaggregation of Revenue [Line Items]
Revenues	278,142	248,010	551,238	473,637
Optical communications \| Datacenter interconnect
Disaggregation of Revenue [Line Items]
Revenues	142,200	100,039	280,280	171,846
Non-optical communications
Disaggregation of Revenue [Line Items]
Revenues	$ 300,298	$ 186,458	$ 531,530	$ 364,371
Non-optical communications \| Product concentration risk \| Revenue from contract with customer benchmark
Disaggregation of Revenue [Line Items]
Revenues, percentage	26.50%	22.40%	25.20%	22.20%
Non-optical communications \| Automotive
Disaggregation of Revenue [Line Items]
Revenues	$ 116,956	$ 104,247	$ 238,904	$ 206,988
Non-optical communications \| Industrial laser
Disaggregation of Revenue [Line Items]
Revenues	41,432	37,542	81,111	72,868
Non-optical communications \| High-performance computing
Disaggregation of Revenue [Line Items]
Revenues	85,556		100,959
Non-optical communications \| Others
Disaggregation of Revenue [Line Items]
Revenues	$ 56,354	$ 44,669	$ 110,556	$ 84,515

Fabrinet 10-Q