Industry Segments and Geographic Area Information - Geographic Area (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Sales:
Net sales	$ 1,100.1	$ 1,083.4	$ 1,054.3	$ 956.3	$ 917.1	$ 970.3	$ 837.5	$ 957.6	$ 4,194.1	$ 3,682.5	$ 3,946.6
Operating Income:
Operating Income									532.3	494.5	526.7
Long-lived Assets:
Long-Lived Assets	3,397.1				3,492.4				3,397.1	3,492.4	3,322.7
Assets held for sale - non-current	177.1				184.1				177.1	184.1
Discontinued Operations, Held-for-Sale | Commercial and Industrial Lighting Business
Long-lived Assets:
Assets held for sale - current	356.6								356.6
Assets held for sale - non-current	177.1				184.1				177.1	184.1
United States
Net Sales:
Net sales									3,809.8	3,356.9	3,546.1
Operating Income:
Operating Income									439.6	436.3	458.7
Long-lived Assets:
Long-Lived Assets	3,038.1				3,113.7				3,038.1	3,113.7	2,950.5
International
Net Sales:
Net sales									384.3	325.6	400.5
Operating Income:
Operating Income									92.7	58.2	68.0
Long-lived Assets:
Long-Lived Assets	$ 359.0				$ 378.7				$ 359.0	$ 378.7	$ 372.2