Represents the number of lawsuits to which the entity is a plaintiff related to a sales contract.

No definition available.

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Namespace Prefix:	ar_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount awarded from other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Publisher FASB
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-Topic 460
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-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12021-110248

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Cash received for the settlement of litigation during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3536-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Contingencies (Details) - WGL $ in Millions		1 Months Ended
Contingencies (Details) - WGL $ in Millions	Jun. 20, 2019 USD ($)	Feb. 28, 2021 USD ($)	Jun. 30, 2019 lawsuit	Mar. 31, 2017 USD ($)
Settled Litigation
Contingencies
Damages awarded	$ 96
Settlement amount received		$ 107
Pending Litigation
Contingencies
Number of lawsuits \| lawsuit			2
Pending Litigation \| Minimum
Contingencies
Damages sought				$ 40