Unaudited Supplemental Pro Forma Financial Information (Detail) - Finisar Corporation - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Revenue	$ 666,331	$ 672,403	$ 1,274,487	$ 1,300,266
Net Earnings (Loss)	$ (29,318)	$ (16,633)	$ (30,956)	$ (147,820)