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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The number of businesses acquired by the entity during the period.

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Acquisitions (Narrative) (Details) $ in Millions		12 Months Ended
Acquisitions (Narrative) (Details) $ in Millions	Dec. 09, 2019 USD ($)	Dec. 31, 2019 USD ($) acquisition	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) acquisition
Business Acquisition [Line Items]
Goodwill, expected to provide a tax benefit		$ 139.0
Contingent consideration, liability		9.2	$ 10.8
Additional consideration including interest paid		1.1	9.3	$ 2.2
Purchase price	$ 20.8
Goodwill added	$ 7.0	566.3	28.1
ECS
Business Acquisition [Line Items]
Purchase price		1,244.3
Goodwill added		559.3
Manufacturer and distributor of innovative home and garden products
Business Acquisition [Line Items]
Purchase price			19.1
Manufacturer and distributor of silt fence
Business Acquisition [Line Items]
Purchase price			2.6
PHC
Business Acquisition [Line Items]
Purchase price			87.4
Goodwill added			26.9
Joint venture
Business Acquisition [Line Items]
Purchase price				2.6
Specialized Products
Business Acquisition [Line Items]
Goodwill added		0.0	26.8
Residential Products and Furniture Products
Business Acquisition [Line Items]
Goodwill, period change				$ 11.3
Residential Products and Furniture Products \| Distributor and installer of geosynthetic products; Flooring products; Surface-critical bent tube components
Business Acquisition [Line Items]
Number of acquisitions \| acquisition				3
Residential Products
Business Acquisition [Line Items]
Goodwill added		$ 566.3	1.3
Goodwill, period change				$ 7.4
Residential Products \| A leader in proprietary specialized foam technology, primarily for the bedding and furniture industries; Manufacturer and distributor of geosynthetic and mine ventilation products
Business Acquisition [Line Items]
Number of acquisitions \| acquisition		2
Furniture Products
Business Acquisition [Line Items]
Goodwill added		$ 0.0	0.0
Goodwill, period change				$ 3.9
Liability for future payments, current
Business Acquisition [Line Items]
Contingent consideration, liability		9.2	0.8
Liability for future payments, long-term
Business Acquisition [Line Items]
Contingent consideration, liability			10.0
Leggett & Platt \| Joint venture
Business Acquisition [Line Items]
Remaining ownership (as a percent)				20.00%
Customer relationships \| ECS
Business Acquisition [Line Items]
Other intangible assets		372.3
Customer relationships \| Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Other intangible assets		378.9	19.4	$ 11.3
Technology \| ECS
Business Acquisition [Line Items]
Other intangible assets		173.3
Technology \| Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Other intangible assets		$ 173.3	$ 4.9	$ 0.0