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

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

+ Details

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

+ Details

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

- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

+ Details

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

- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: 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=66902209&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOrSaleOfEquity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

No definition available.

+ Details

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

- Definition

The period of used to calculate the volume weighted average price used to calculate the value per share of the acquiree to be paid as consideration to acquire the entity.

+ References

No definition available.

+ Details

Name:	xon_BusinessCombinationConsiderationToBeTransferredPeriodofVolumeWeightedAveragePriceUsedtoCalculateValueperAcquireeShare
Namespace Prefix:	xon_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The value per share of the acquiree to be paid as consideration to acquire the entity.

+ References

No definition available.

+ Details

Name:	xon_BusinessCombinationConsiderationToBeTransferredValueperAcquireeShare
Namespace Prefix:	xon_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares of equity interested issued or issuable per share of acquiree to acquire entity.

+ References

No definition available.

+ Details

Name:	xon_BusinessCombinationEquityInterestsIssuedorIssuableNumberofSharesIssuedperAcquireeShare
Namespace Prefix:	xon_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The period subsequent to the acquisition during which a portion of collaboration payments received from previously existing collaborations will be paid to former stockholders of the acquired entity.

+ References

No definition available.

+ Details

Name:	xon_BusinessCombinationPeriodSubsequenttoAcquisitionDuringWhichAPortionofCollaborationPaymentsReceivedWillBePaidtoFormerStockholdersofAcquiredEntity
Namespace Prefix:	xon_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percent of collaboration payments received pursuant to a collaboration agreement for upfront fees, milestones and royalties which will be paid to another party.

+ References

No definition available.

+ Details

Name:	xon_CollaborationArrangementPercentOfCollaborationPayments
Namespace Prefix:	xon_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Notice period for contract termination of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	xon_LesseeLeasingArrangementsOperatingLeasesContractTerminationNoticePeriod
Namespace Prefix:	xon_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=xon_OragenicsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=xon_OragenicsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LeaseArrangementTypeAxis=us-gaap_LandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=xon_GenVecInc.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended
	Apr. 30, 2017	Jan. 31, 2017	Mar. 31, 2017
Subsequent Event [Line Items]
Total future minimum lease payments due under operating leases			$ 52,372
Oragenics, Inc. \| Subsequent Event
Subsequent Event [Line Items]
Total principal under commitment letter for unsecured loan	$ 2,400
Term for unsecured loan	2 years
Debt instrument, interest rate, stated percentage	12.00%
Conditional term \| Oragenics, Inc. \| Subsequent Event
Subsequent Event [Line Items]
Gross proceeds from an equity financing	$ 2,700
Land \| Subsequent Event
Subsequent Event [Line Items]
Total future minimum lease payments due under operating leases	$ 4,100
Notice period to terminate lease	6 months
GenVec, Inc.
Subsequent Event [Line Items]
Number of shares of common stock to be issued per share of acquiree's common stock		0.297
Calculated value of share of acquiree's common stock (in usd per share)		$ 7.00
Period used to calculate volume weighted average price		5 days
Percent of collaboration payments		50.00%
Period during which a portion of collaboration payments received will be paid to former stockholders of acquiree		3 years