The maximum number of resale share registered.

No definition available.

Name:	atch_MaximumNumberOfResaleShareRegistered
Namespace Prefix:	atch_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares issued during period in lieu of settlement of obligations.

+ References

No definition available.

+ Details

Name:	atch_StockIssuedDuringPeriodSharesIssuedForSettlementOfObligations
Namespace Prefix:	atch_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesIssuedPricePerShare
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Value of stock issued in lieu of cash for services contributed to the entity. Value of the stock issued includes, but is not limited to, services contributed by vendors and founders.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

+ Details

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

- Details

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

- Details

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

- Details

Name:	srt_CounterpartyNameAxis=atch_WilsonDavisSellersMember
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SUBSEQUENT EVENTS (Details) - USD ($)				3 Months Ended
SUBSEQUENT EVENTS (Details) - USD ($)	Apr. 08, 2024	Apr. 04, 2024	Feb. 09, 2024	Mar. 31, 2024	May 14, 2024	Dec. 31, 2023	Nov. 03, 2023	Dec. 31, 2022
Subsequent Event [Line Items]
Common Stock, par value (in Dollars per share)				$ 0.0001		$ 0.0001		$ 0.0001
Common stock issued to settled vendor obligations				$ 1,513,100
Price per public share (in Dollars per share)				$ 10			$ 10.73
Shares issued in settlement of obligations (in shares)			2,201,010
Subsequent event
Subsequent Event [Line Items]
Shares issued in settlement of obligations (in shares)			2,201,010
Maximum number of resale shares registered					37,885,852
Calabrese Consulting LLC \| Subsequent event
Subsequent Event [Line Items]
Common Stock, par value (in Dollars per share)		$ 2.00
Common stock issued to settled vendor obligations (in shares)		32,188
Common stock issued to settled vendor obligations		$ 64,236
Wilson-Davis Sellers \| Subsequent event
Subsequent Event [Line Items]
Shares issued in settlement of obligations (in shares)	145,210