Limit amount of net tangible assets.

No definition available.

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- Definition

Proceeds from offering deposited in trust account deposited into trust account during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	atacu_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Refers to carrying amount of trust account deposit as on balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	atacu_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

The cash inflow associated with the amount received from entity's first offering of stock to the public.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

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

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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

- Details

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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Balance Type:
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- Details

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- Details

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Organization and Plan of Business Operations (Details Narrative) - USD ($)					4 Months Ended	9 Months Ended
	Aug. 21, 2017	Aug. 16, 2017	Aug. 14, 2017	Aug. 14, 2017	Sep. 30, 2016	Sep. 30, 2017	May 30, 2017	Jun. 09, 2016
Net proceeds from offering			$ 41,476,000
Gross proceeds from offering						$ 40,000,000
Limit of net tangible assets						5,000,001
Share price (in dollars per share)							$ 0.02	$ 0.02
American Stock Transfer & Trust LLC [Member]
Proceeds from offering deposited in trust account deposited into trust account	$ 45,135,000
American Stock Transfer & Trust LLC [Member] \| Minimum [Member]
Trust account deposit						$ 800,000
Share price (in dollars per share)						$ 0.20
American Stock Transfer & Trust LLC [Member] \| Maximum [Member]
Trust account deposit						$ 1,600,000
Share price (in dollars per share)						$ 0.40
Public Offering [Member]
Number of unit issued			4,000,000	4,000,000
Unit price (in dollars per share)			$ 10.00	$ 10.00
Private Placement [Member]
Number of unit issued						250,000
Private Placement [Member] \| Company's shareholders & Chardan Capital Markets, LLC [Member]
Number of unit issued			320,000
Unit price (in dollars per share)			$ 10.00	$ 10.00
Over-Allotment Option [Member] \| Company's shareholders & Chardan Capital Markets, LLC [Member]
Number of unit issued			21,250
Over-Allotment Option [Member] \| Underwriter [Member]
Number of unit issued	21,250	425,000
Gross proceeds from offering	$ 212,500	$ 4,250,000
Over-Allotment Option [Member] \| American Stock Transfer & Trust LLC [Member] \| Minimum [Member]
Trust account deposit						$ 920,000
Share price (in dollars per share)						$ 0.20
Over-Allotment Option [Member] \| American Stock Transfer & Trust LLC [Member] \| Maximum [Member]
Trust account deposit						$ 1,840,000
Share price (in dollars per share)						$ 0.40