Number of milestone payments.

No definition available.

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Namespace Prefix:	ctic_
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Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

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

- Definition

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

+ References

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

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- 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

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- Definition

Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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- Definition

Revenue from multiple-deliverable arrangements that include licensing fees and services revenue. Licensing revenue is consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity. Services revenue may be derived by providing other, nonspecified, services during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(d),(e))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=ctic_BaxaltaIncorporatedAndAffiliatesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ctic_MilestonePaymentsByMilestoneTypeAxis=ctic_Persist2MilestoneMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	ctic_MilestonePaymentsByMilestoneTypeAxis=ctic_EuropeanMedicinesAgencyMilestoneMember
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Milestone Payments (Detail)	3 Months Ended			9 Months Ended
Milestone Payments (Detail)	Sep. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($) payment
Debt Instrument [Line Items]
License and contract revenue	$ 3,447,000		$ 219,000	$ 45,009,000	$ 2,383,000
Borrowing Associated With License Agreement
Debt Instrument [Line Items]
Milestone payment						$ 32,000,000.0
Milestone advance interest rate						9.00%
Baxalta
Debt Instrument [Line Items]
Gain on termination of agreement	$ 4,200,000			$ 4,200,000
Baxalta \| Borrowing Associated With License Agreement
Debt Instrument [Line Items]
Number of milestone payments \| payment						2
License and contract revenue		$ 32,000,000
Baxalta \| PERSIST-2 Milestone \| Borrowing Associated With License Agreement
Debt Instrument [Line Items]
Milestone payment						$ 20,000,000.0
Baxalta \| European Medicines Agency Milestone \| Borrowing Associated With License Agreement
Debt Instrument [Line Items]
Milestone payment						$ 12,000,000.0