Lessor, Operating Lease, Days After Agreement Execution, Payments Due

No definition available.

Name:	atex_LessorOperatingLeaseDaysAfterAgreementExecutionPaymentsDue
Namespace Prefix:	atex_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Lessor Operating Lease Payments Received

+ References

No definition available.

+ Details

Name:	atex_LessorOperatingLeasePaymentsReceived
Namespace Prefix:	atex_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number Of People Covered By Network

+ References

No definition available.

+ Details

Name:	atex_NumberOfPeopleCoveredByNetwork
Namespace Prefix:	atex_
Data Type:	xbrli:integerItemType
Balance Type:	na
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

Name:	us-gaap_LessorLeaseDescriptionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of lease payments to be received by lessor for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919396-209981

+ Details

Name:	us-gaap_LessorOperatingLeasePaymentsToBeReceived
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Term of lessor's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919359-209981

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_LessorOperatingLeaseTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	srt_CounterpartyNameAxis=atex_AmerenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=atex_EvergyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
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Nature of Operations (Details) people in Millions, $ in Millions	1 Months Ended
	Oct. 31, 2021 USD ($)	Sep. 30, 2021 USD ($) people	Feb. 28, 2021 USD ($) people	Dec. 31, 2020 USD ($) people	Mar. 31, 2022
Lessor, Lease, Description [Line Items]
Number of people \| people			3.6	7.5
Lease term				30 years
Lease extension		10 years		10 years
Scheduled prepayments				$ 47.7
Days after agreement execution, payments due		30 days
Ameren
Lessor, Lease, Description [Line Items]
Lease term					30 years
Lease payments received	$ 17.2	$ 5.4	$ 0.3
Evergy
Lessor, Lease, Description [Line Items]
Number of people \| people		3.9
Lease term		20 years
Scheduled prepayments		$ 30.2
Minimum
Lessor, Lease, Description [Line Items]
Lease term		40 years		40 years
Lease extension					3 years