Discontinued Operations - Financial Results (Details) - Lighting Products - Discontinued Operations, Held-for-sale or Disposed of by Sale - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Mar. 31, 2019	Mar. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue, net	$ 109.4	$ 376.0
Cost of revenue, net	82.5	287.5
Gross profit	26.9	88.5
Research and development	8.8	27.4
Sales, general and administrative	21.2	68.2
Amortization or impairment of acquisition-related intangibles	2.0	9.1
Goodwill impairment charges	197.6	197.6
Loss on disposal or impairment of long-lived assets	1.8	2.1
Other operating expense	0.5	1.9
Operating loss	(205.0)	(217.8)
Non-operating income	(0.2)	(0.5)
Loss before income taxes	(204.8)	(217.3)
Income tax expense	0.6	0.7
Net loss	$ (205.4)	$ (218.0)