CONSOLIDATED STATEMENTS OF OPERATIONS (unaudited) - USD ($) shares in Millions, $ in Millions		3 Months Ended		6 Months Ended
		Dec. 26, 2015	Dec. 27, 2014	Dec. 26, 2015	Dec. 27, 2014
Income Statement [Abstract]
Net revenue		$ 218.3	$ 210.5	$ 430.9	$ 429.5
Cost of sales		148.5	141.7	292.5	288.5
Amortization of acquired technologies		1.7	1.9	3.4	3.8
Gross profit		68.1	66.9	135.0	137.2
Operating expenses:
Research and development		35.0	35.1	69.4	70.1
Selling, general and administrative		25.8	31.2	59.8	59.5
Restructuring and related charges		1.1	3.8	2.1	5.6
Total operating expenses		61.9	70.1	131.3	135.2
Income (loss) from operations		6.2	(3.2)	3.7	2.0
Unrealized loss on derivative liability		(2.4)	0.0	(0.2)	0.0
Interest and other (expense) income, net		(0.5)	(0.1)	(0.7)	(0.4)
Income (loss) before income taxes		3.3	(3.3)	2.8	1.6
Provision for income taxes		0.5	0.8	0.2	1.4
Net income (loss)		2.8	(4.1)	2.6	0.2
Cumulative dividends on Series A preferred stock		(0.2)	0.0	(0.3)	0.0
Accretion of Series A preferred stock		(2.0)	0.0	(11.7)	0.0
Net income (loss) available to common shareholders		$ 0.6	$ (4.1)	$ (9.4)	$ 0.2
Net (loss) income per share attributable to common shareholders:
Basic (usd per share)	[1]	$ 0.01	$ (0.07)	$ (0.16)	$ 0.00
Diluted (usd per share)	[1]	$ 0.01	$ (0.07)	$ (0.16)	$ 0.00
Shares used in per share calculation attributable to common shareholders:
Basic (in shares)	[1]	59.0	58.8	58.9	58.8
Diluted (in shares)	[1]	59.2	58.8	58.9	58.8

[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. (“we”, “our”, “Company” or “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 income (loss) per share for the three and six months ended December 27, 2014 is calculated using the shares of Lumentum common stock outstanding on August 1, 2015, as if such shares were outstanding for the entire period.