Equity Method Investment, Increase (Decrease) In Ownership Percentage Upon Exchange Transaction

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- Definition

Net Gain (Loss) On Exchange Of Equity Affiliate Investments

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Number Of Facilities Acquired

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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.

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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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No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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- Definition

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

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

Amount of gain (loss) on sale or disposal of an equity method investment.

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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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- Definition

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

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No definition available.

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Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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- Definition

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

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No definition available.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Acquisitions (Narrative) (Details) $ in Millions, ¥ in Billions					3 Months Ended				12 Months Ended
	Apr. 17, 2020 USD ($) production_facility	May 01, 2019 USD ($)	Apr. 26, 2018 USD ($)	Apr. 26, 2018 CNY (¥)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2020 USD ($) acquisition	Sep. 30, 2019 USD ($) acquisition	Sep. 30, 2018 USD ($) acquisition
Property, Plant and Equipment [Line Items]
Additions to plant and equipment									$ 2,509.0	$ 1,989.7	$ 1,568.4
Equity issued related to asset acquisition									17.1
Business Acquisition [Line Items]
Business combinations, goodwill acquired during period									71.1	48.6
Gain on exchange of equity affiliate investments		$ 29.1			$ 0.0	$ 29.1	$ 0.0	$ 0.0	$ 0.0	$ 29.1	0.0
Air Products Lu An Changzhi Co Ltd
Property, Plant and Equipment [Line Items]
Equity issued related to asset acquisition											$ 227.4
Joint Venture \| Air Products Lu An Changzhi Co Ltd
Property, Plant and Equipment [Line Items]
Ownership interest by Air Products (percent)				60.00%
Additions to plant and equipment			$ 235.0	¥ 1.5
Equity issued related to asset acquisition			$ 227.0	1.4
Production Plants
Business Acquisition [Line Items]
Number of hydrogen production plants acquired \| production_facility	5
Acquisition of hydrogen production plants	$ 580.0
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Number of business combinations completed in period \| acquisition									3	3	8
Business combinations, aggregate purchase price, net of cash acquired									$ 185.4	$ 126.6	$ 355.4
Business combinations, plant and equipment acquired during the period									71.2
Business combinations, goodwill acquired during period									71.1
Business combinations, recognized identifiable intangible assets									50.7
Business combinations, tax deductible goodwill									$ 8.1
Acquired finite-lived intangible assets, weighted-average useful life									19 years
WuXi Hi-Tech Gas Co., Ltd.
Business Acquisition [Line Items]
Interest acquired in exchange transaction (percent)		50.00%
Gain from revaluation of previously held equity interest to acquisition date fair value		$ 15.0
Estimated acquisition date fair value of previously held equity interest		$ 27.0
High-Tech Gases (Beijing) Co., Ltd.
Business Acquisition [Line Items]
Ownership interest percentage											50.00%
Decrease in ownership interest in exchange transaction (percent)		50.00%
Gain from disposal of interest in equity method investment		$ 14.1
WuXi Hi-Tech Gas Co., Ltd.
Business Acquisition [Line Items]
Ownership interest percentage											50.00%
Lu'An Loan To Joint Venture \| Loans Payable
Property, Plant and Equipment [Line Items]
Loan to joint venture, face amount \| ¥				¥ 2.6