Intangible assets net derecognized.

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=123455525&loc=d3e2207-128464

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- Definition

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.

+ References

No definition available.

+ Details

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Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Finite Lived Intangible Assets [Line Items]
Amortization Expenses	$ 92.3	$ 5.4	$ 261.6	$ 16.7
Eastern U.S. Gypsum Distribution Operations
Finite Lived Intangible Assets [Line Items]
Intangible assets, net derecognized			0.5
BMC Merger and Current Year Acquisitions
Finite Lived Intangible Assets [Line Items]
Intangible assets in connection with acquisition	1,800.0		$ 1,800.0
Weighted average useful lives of the acquired intangible assets			11 years 1 month 6 days
BMC Merger and Current Year Acquisitions \| Customer Relationships
Finite Lived Intangible Assets [Line Items]
Intangible assets in connection with acquisition	1,500.0		$ 1,500.0
Weighted average useful lives of the acquired intangible assets			11 years 3 months 18 days
BMC Merger and Current Year Acquisitions \| Trade Names
Finite Lived Intangible Assets [Line Items]
Intangible assets in connection with acquisition	149.8		$ 149.8
Weighted average useful lives of the acquired intangible assets			7 years
BMC Merger and Current Year Acquisitions \| Developed Technology
Finite Lived Intangible Assets [Line Items]
Intangible assets in connection with acquisition	97.2		$ 97.2
Weighted average useful lives of the acquired intangible assets			9 years
BMC Merger and Current Year Acquisitions \| Non-compete Agreements
Finite Lived Intangible Assets [Line Items]
Intangible assets in connection with acquisition	$ 9.8		$ 9.8
Weighted average useful lives of the acquired intangible assets			5 years 8 months 12 days