Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)
Notes Tables
Notes Details

FAIR VALUE MEASUREMENT - Fair value of other equity investments (Details)

v3.19.1

FAIR VALUE MEASUREMENT - Fair value of other equity investments (Details)		12 Months Ended
	Jun. 20, 2018 CNY (¥)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 CNY (¥)	Dec. 31, 2017 CNY (¥)
FAIR VALUE MEASUREMENT
Other equity investments			¥ 66,390,898	¥ 70,021,700
Gain from change in fair value		$ 399,971	2,750,000
ApplySquare Education & Technology Co., Ltd. ("ApplySquare")
FAIR VALUE MEASUREMENT
Other equity investments			22,471,700	19,721,700
Gain from change in fair value	¥ 2,750,000		2,750,000
ApplySquare Education & Technology Co., Ltd. ("ApplySquare") \| Nonrecurring basis
FAIR VALUE MEASUREMENT
Other equity investments			22,471,700
ApplySquare Education & Technology Co., Ltd. ("ApplySquare") \| Nonrecurring basis \| Level 3
FAIR VALUE MEASUREMENT
Other equity investments			22,471,700
Beijing GlobalWisdom Information Technology Co., Ltd. ("GlobalWisdom")
FAIR VALUE MEASUREMENT
Other equity investments			5,919,198	¥ 12,300,000
Impairment loss recorded			6,380,802
Beijing GlobalWisdom Information Technology Co., Ltd. ("GlobalWisdom") \| Nonrecurring basis
FAIR VALUE MEASUREMENT
Other equity investments			5,919,198
Beijing GlobalWisdom Information Technology Co., Ltd. ("GlobalWisdom") \| Nonrecurring basis \| Level 3
FAIR VALUE MEASUREMENT
Other equity investments			¥ 5,919,198

- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714

+ Details

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

- Definition

Amount of impairment loss on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714

+ Details

Name:	us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueImpairmentLossAnnualAmount
Namespace Prefix:	us-gaap_
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

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

- Definition

Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714

+ Details

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

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=atai_ApplysquareEducationTechnologyCo.Ltd.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=atai_BeijingGlobalwisdomInformationTechnologyCo.Ltd.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: