Debt instrument extend date.

No definition available.

Name:	atnx_DebtInstrumentExtendDate
Namespace Prefix:	atnx_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument variable rate basis floor.

+ References

No definition available.

+ Details

Name:	atnx_DebtInstrumentVariableRateBasisFloor
Namespace Prefix:	atnx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility percentage of periodic payment year one.

+ References

No definition available.

+ Details

Name:	atnx_LineOfCreditFacilityPercentageOfPeriodicPaymentYearOne
Namespace Prefix:	atnx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility percentage of periodic payment year two.

+ References

No definition available.

+ Details

Name:	atnx_LineOfCreditFacilityPercentageOfPeriodicPaymentYearTwo
Namespace Prefix:	atnx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the frequency of periodic payments, which may be presented in a variety of ways (for example, monthly, quarterly, annually).

+ References

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=atnx_ChongqingMaliuRiversideDevelopmentAndInvestmentCoLTDMember
Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=atnx_SeniorSecuredLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
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Debt and Lease Obligations - Additional Information (Detail) $ in Thousands, ¥ in Millions	3 Months Ended			12 Months Ended
	Mar. 31, 2020 USD ($)	Jun. 30, 2019 CNY (¥)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Mortgage payment extended date	Dec. 31, 2020
Chongqing Maliu Riverside Development and Investment Co., LTD (“CQ”)
Debt Instrument [Line Items]
Line of credit facility percentage of periodic payment year one		20.00%
Line of credit facility percentage of periodic payment year two		30.00%
Line of credit frequency of payments	The Company is required to repay the principal amount with accrued interest within three years after the plant receives the U.S. Current Good Manufacturing Practices (“cGMP”) certification, with 20% of the total loan with accrued interest is due within the first twelve months following receiving the certification, 30% of the total loan with accrued interest due within twenty-four months, and the remaining balance with accrued interest due within thirty-six months.
Line of credit due	$ 6,055				$ 5,731
China \| Chongqing Maliu Riverside Development and Investment Co., LTD (“CQ”)
Debt Instrument [Line Items]
Long-term line of credit	$ 7,200	¥ 50.0
Unsecured, Subordinated Bank Loan from China Merchants Bank \| China
Debt Instrument [Line Items]
Convertible bonds, aggregate principal value			$ 700
Debt maturity date			Dec. 11, 2019
Interest rate			5.70%
Senior Secured Loan
Debt Instrument [Line Items]
Convertible bonds, aggregate principal value				$ 50,000
Debt maturity date				Jun. 30, 2023
Senior Secured Loan \| LIBOR
Debt Instrument [Line Items]
Debt variable rate basis floor				2.00%
Basis spread on variable rate				9.00%