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- Definition

Business Combination, Consideration Transferred, Equity Interests Issuable Per Share, Shares

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- Definition

Deferred Tax Asset, Step Up In Tax Basis of The Underlying Assets

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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- Definition

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

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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

The expenses and losses recorded for each transaction with the acquiree that was recognized separately from the acquisition of assets and assumptions of liabilities in the business combination.

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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

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- Definition

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

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- Definition

The cash outflow associated with the purchase of noncontrolling interest during the period.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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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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AmeriGas Merger, Acquisitions and Dispositions - Narrative (Details) $ / shares in Units, $ in Millions			3 Months Ended		12 Months Ended
	Aug. 21, 2019 USD ($) $ / shares shares	Aug. 01, 2019 USD ($) shares	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Sep. 30, 2019 USD ($) shares	Sep. 30, 2018 USD ($) propane_distribution_business	Jul. 31, 2020
Statement [Line Items]
Impairment of assets held-for-sale				$ 52
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations \| HVAC Business
Statement [Line Items]
Loss on sale of business			$ 2
Jointly Owned Electricity Generation Plant
Statement [Line Items]
Proportionate ownership share, percent (as a percentage)							5.97%
Merger Sub
Statement [Line Items]
Total cash paid	$ 529
Incentive distribution, distribution	2,228
After tax transaction costs	8
Operating expenses	6
Deferred tax asset, step up in tax basis of the underlying assets	$ 512				$ 512
Merger Sub \| Common Stock
Statement [Line Items]
Consideration paid (in shares) \| shares	34,612,847	34,613,000			34,613,000
CMG
Statement [Line Items]
After tax transaction costs					$ 15
Total cash paid		$ 1,284
Merger Agreement, Proposed Consideration One \| Merger Sub \| Common Stock
Statement [Line Items]
Business combination, consideration transferred, equity interests issuable per acquiree share (in shares) \| shares	0.6378
Merger Agreement, Proposed Consideration Two \| Merger Sub \| Common Stock
Statement [Line Items]
Business combination, consideration transferred, equity interests issuable per acquiree share (in shares) \| shares	0.500
Merger Agreement, Proposed Consideration Two \| Merger Sub \| Cash Without Interest
Statement [Line Items]
Business combination, consideration transferred, equity interests issuable per share (in dollars per share) \| $ / shares	$ 7.63
Merger Agreement, Proposed Consideration Three \| Merger Sub \| Cash Without Interest
Statement [Line Items]
Business combination, consideration transferred, equity interests issuable per share (in dollars per share) \| $ / shares	$ 35.325
AmeriGas Propane
Statement [Line Items]
Incentive distribution, distribution						$ 13
Total cash paid						$ 10
Number of retail propane distribution businesses acquired \| propane_distribution_business						2
Affiliated Entity \| CMG \| Pennant
Statement [Line Items]
Percentage of voting interests acquired (as a percentage)		47.00%			47.00%