Intangible Assets, Gross, (Including Goodwill)

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For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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Gross carrying amount before accumulated amortization as of the balance sheet date to an asset acquired in a business combination representing a favorable existing relationship with customers having a finite beneficial life.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after accumulated impairment loss 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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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 foreign currency translation gain (loss) which increases (decreases) an asset, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through registration of a trade name to gain or protect exclusive use thereof for a projected indefinite period of benefit.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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Amount after accumulated amortization of finite-lived and indefinite-lived intangible assets classified as other.

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No definition available.

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Identifiable Intangible Assets Schedule of Intangible Assets and Goodwill (Details) - USD ($)	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Indefinite-lived intangible assets:
Goodwill	$ 115,100,000	$ 99,800,000	$ 95,700,000
Intangible Assets, Gross, (Including Goodwill)	770,300,000	760,400,000
Accumulated amortization:
Intangible Assets, Net (Excluding Goodwill)	392,500,000	408,900,000
Goodwill, Acquired During Period	12
Indefinite-lived Intangible Assets, Foreign Currency Translation Gain (Loss)	3,200,000	3,800,000
Krausz
Indefinite-lived intangible assets:
Goodwill	91,200,000
Infrastructure
Indefinite-lived intangible assets:
Goodwill	103,000,000
Mueller Technologies [Member]
Indefinite-lived intangible assets:
Goodwill	12,100,000
Krausz
Accumulated amortization:
Goodwill, Acquired During Period	0	300,000
i2O
Accumulated amortization:
Goodwill, Acquired During Period	12,100,000	0
Business Combination-Related Identifiable Intangible [Member]
Accumulated amortization:
Accumulated Amortization	387,800,000	362,200,000
Net book value	382,500,000	398,200,000
Trademarks and Trade Names [Member]
Indefinite-lived intangible assets:
Trade names and trademarks	273,800,000	271,600,000
Software and Software Development Costs [Member]
Capitalized external-use software:
Capitalized Computer Software, Gross	34,100,000	31,500,000
Accumulated amortization	24,100,000	20,800,000
Net book value	10,000,000.0	10,700,000
Technology-Based Intangible Assets [Member]
Finite-lived intangible assets:
Technology	123,500,000	118,500,000
Accumulated amortization:
Accumulated Amortization	85,800,000	81,000,000.0
Customer Relationships [Member]
Finite-lived intangible assets:
Customer relationships and other	373,000,000.0	370,200,000
Accumulated amortization:
Accumulated Amortization	$ 302,000,000.0	$ 281,200,000