Fair value assumptions expected percentage of warrants to be exercised.

No definition available.

Name:	idra_FairValueAssumptionsExpectedPercentageOfWarrantsToBeExercised
Namespace Prefix:	idra_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	idra_FairValueOfAssetsAndLiabilitiesAdditionalTextualAbstract
Namespace Prefix:	idra_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	idra_FairValueOfAssetsAndLiabilitiesTextualAbstract
Namespace Prefix:	idra_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Increase (decrease) in fair value of warrant liability.

+ References

No definition available.

+ Details

Name:	idra_IncreaseDecreaseInFairValueOfWarrantLiability
Namespace Prefix:	idra_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Ownership limitation for warrant exercise.

+ References

No definition available.

+ Details

Name:	idra_OwnershipLimitationForWarrantExercise
Namespace Prefix:	idra_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The exercise price of each class of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i)(4))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Subparagraph 4

-Article 4

+ Details

Name:	us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights
Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- Definition

Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph a

-Clause 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

+ Details

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

- Definition

Agreed upon price for the exchange of the underlying asset.

+ References

+ Details

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

- Definition

Description of where the gains or losses, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), are included in earnings or the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

Fair Value of Assets and Liabilities (Details Textual) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Sep. 30, 2012	Dec. 31, 2011	Nov. 30, 2011
Fair value of assets and liabilities (Textual) [Abstract]
Expected warrant exercise price	$ 1.46	$ 1.46		$ 1.46	$ 1.46
Initial exercise price						1.63
Percentage of ownership limitation	19.99%			19.99%	19.99%
Percentage of expected warrants to be exercised	100.00%	100.00%		100.00%	100.00%
Fair value of warrants	$ 1,072			$ 1,072	$ 1,178
Non-operating (income)/expense	(109)	(1,318)	1,321	(106)
Fair value of assets and liabilities (Additional Textual) [Abstract]
Significant changes in fair value of the warrants in the future, resulting in material non operating charges and credits in some periods				The Company expects that the fair value of the warrants will vary significantly in the future resulting in material non-operating charges and credits in some periods.
Warrant [Member]
Fair value of assets and liabilities (Textual) [Abstract]
Fair value of warrants	$ 1,072	$ 1,181		$ 1,072	$ 1,178
Minimum [Member]
Fair value of assets and liabilities (Textual) [Abstract]
Expected warrant exercise price	$ 1.46	$ 1.46		$ 1.46	$ 1.46