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.

No definition available.

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- Definition

Nominal number of units used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

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Derivative Instruments and Hedging Activities - Schedule of Notional Amounts (Details) € in Millions, kWh in Millions, gal in Millions, DTH in Millions, $ in Millions	Mar. 31, 2021 USD ($) gal DTH kWh	Mar. 31, 2021 EUR (€) gal DTH kWh	Sep. 30, 2020 USD ($) gal kWh DTH	Sep. 30, 2020 EUR (€) gal kWh DTH	Mar. 31, 2020 USD ($) gal kWh DTH	Mar. 31, 2020 EUR (€) gal kWh DTH
Interest rate swaps
Derivative [Line Items]
Notional amount	$ 1,302	€ 300	$ 1,344	€ 300	$ 1,351	€ 300
Forward foreign currency exchange contracts
Derivative [Line Items]
Notional amount	$ 384	€ 173	$ 511	€ 173	$ 460	€ 173
Regulated Utility Operations \| Commodity contracts \| Natural Gas
Derivative [Line Items]
Notional amount (in units)	12	12	22	22	11	11
Unregulated Operation \| Commodity contracts \| LPG
Derivative [Line Items]
Notional amount (in units) \| gal	557	557	846	846	816	816
Unregulated Operation \| Commodity contracts \| Electricity \| Long
Derivative [Line Items]
Notional amount (in units) \| kWh	4,773	4,773	4,705	4,705	3,663	3,663
Unregulated Operation \| Natural gas futures, forward and pipeline contracts (in dekatherms) \| Natural Gas
Derivative [Line Items]
Notional amount (in units)	338	338	339	339	343	343