Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 28, 2013	Sep. 28, 2013	Jun. 27, 2015		Jun. 28, 2014		Jun. 29, 2013
Numerator:
Net (loss) income	$ (15.8)	$ 12.2	$ (4.1)	$ 4.3	$ (6.7)	$ 4.8	$ 3.9	$ 8.7	$ (3.4)		$ 10.7		$ 6.5
Denominator
Weighted-average number of common shares outstanding-Basic and diluted	58.8	58.8	58.8	58.8	58.8	58.8	58.8	58.8	58.8	[1]	58.8	[1]	58.8	[1]
Net loss per share - basic and diluted (usd per share)	$ (0.27)	$ 0.21	$ (0.07)	$ 0.07	$ (0.11)	$ 0.08	$ 0.06	$ 0.15	$ (0.06)	[1]	$ 0.18	[1]	$ 0.11	[1]

[1] On August 1, 2015, JDS Uniphase Corporation (“JDSU”) distributed 47.1 million shares, or 80.1% of the outstanding shares of common stock of Lumentum Holdings Inc. (“Lumentum”) to existing holders of JDSU common stock. JDSU was renamed Viavi Solutions Inc. (“Viavi”) and at the time of the distribution, retained 11.7 million shares, or 19.9% of Lumentum’s outstanding shares. Basic and diluted net (loss) income per share for all periods through June 27, 2015 is calculated using the shares of Lumentum common stock outstanding on August 1, 2015. Refer to "Note 4. Earnings Per Share" to the audited annual combined financial statements for more detail.