Estimated aggregate of two potential payment received as consideration.

No definition available.

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- Definition

Estimated first potential payment received as consideration.

+ References

No definition available.

+ Details

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- Definition

Estimated second potential payment received as consideration.

+ References

No definition available.

+ Details

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Namespace Prefix:	agen_
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- Definition

License agreement period.

+ References

No definition available.

+ Details

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- Definition

Non-cash consideration excluded from transaction price.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Non-cash contingent service consideration.

+ References

No definition available.

+ Details

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Namespace Prefix:	agen_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Percentage Of royalty on net sales in exchange for license.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Purchased assets carrying value net.

+ References

No definition available.

+ Details

Name:	agen_PurchasedAssetsCarryingValueNet
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Balance Type:	debit
Period Type:	instant

- Definition

Sale of productive assets and cash consideration received on transaction.

+ References

No definition available.

+ Details

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

- Definition

Sale of productive assets and stock consideration received on transaction.

+ References

No definition available.

+ Details

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

- Definition

Sale of productive assets and stock consideration transaction expenses.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Transaction contract assets.

+ References

No definition available.

+ Details

Name:	agen_TransactionContractAssets
Namespace Prefix:	agen_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of contingent consideration recognized as part of consideration transferred in asset acquisition.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 50
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480060/805-50-25-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 50
-Name Accounting Standards Codification
-Section 30
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480027/805-50-30-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 50
-Name Accounting Standards Codification
-Section 30
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480027/805-50-30-2

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

- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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

- Definition

The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 440
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478522/954-440-50-1

+ Details

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

- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-3A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-3A

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

- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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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Data Type:	xbrli:sharesItemType
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

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

- Details

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- Details

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Sale of Manufacturing Facilities to Zydus (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Jan. 15, 2026	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on Zydus asset sale		$ (40,379)	$ 0
Twelve-month escrow held		7,500		$ 0
Zydus transaction contract assets		40,000		$ 0
Purchase Agreement [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on Zydus asset sale		(40,400)
Purchased assets carrying value net	$ 70,900
Purchase Agreement [Member] \| Zydus Lifesciences Ltd [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration allocated to sale of asset	$ 8,800
License Agreement [Member] \| Zydus Pharmaceuticals Inc [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage of royalty on net sales in exchage for license	5.00%
License agreement period	10 years
Securities Purchase Agreement [Member] \| Zydus Lifesciences Ltd [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash consideration received	$ 7,200
Securities Purchase Agreement [Member] \| Zynext Ventures USA LLC [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of shares issued in transaction	2,133,333
Consideration received in transaction	$ 16,000
Sale price per share	$ 7.5
Zydus Agreements [Member] \| Zydus Lifesciences Ltd [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash consideration received	$ 91,000	91,000
Transaction expenses	5,800	5,800
Twelve-month escrow held	7,500	7,500
Purchased Assets [Member] \| Purchase Agreement [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total consideration	111,300
Purchased Assets [Member] \| Purchase Agreement [Member] \| Zydus Pharmaceuticals Inc [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Asset purchase, contingent consideration amount	50,000
Non-cash contingent service consideration	50,000
Estimated first potential payment received as consideration		20,000
Estimated second potential payment received as consideration		20,000
Estimated aggregate of two potential payment received as consideration		40,000
Non-cash consideration excluded from transaction price		$ 10,000
Purchased Assets [Member] \| Zydus Agreements [Member] \| Zydus Lifesciences Ltd [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash consideration received	$ 71,400