<?xml version="1.0" encoding="utf-8"?>
<FilingSummary xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <Version>2.4.0.8</Version>
  <ProcessingTime />
  <ReportFormat>Html</ReportFormat>
  <ContextCount>60</ContextCount>
  <ElementCount>143</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>23</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>6</UnitCount>
  <MyReports>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>100000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DocumentDocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
    </Report>
    <Report>
      <IsDefault>true</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>100010 - Statement - Condensed Consolidated Balance Sheets (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsUnaudited</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>100020 - Statement - Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsUnauditedParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>100030 - Statement - Condensed Consolidated Statements of Operations (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperationsUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Operations (Unaudited)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>100040 - Statement - Condensed Consolidated Statements of Comprehensive Loss (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveLossUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Comprehensive Loss (Unaudited)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>100050 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlowsUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Cash Flows (Unaudited)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>100060 - Disclosure - Description of Business and Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureDescriptionOfBusinessAndSummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Description of Business and Summary of Significant Accounting Policies</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>100070 - Disclosure - Inventory</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureInventory</Role>
      <ShortName>Inventory</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>100080 - Disclosure - Long-term Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureLongTermDebt</Role>
      <ShortName>Long-term Debt</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>100090 - Disclosure - Legal Proceedings</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureLegalProceedings</Role>
      <ShortName>Legal Proceedings</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>100100 - Disclosure - Share-based Compensation Expense</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureShareBasedCompensationExpense</Role>
      <ShortName>Share-based Compensation Expense</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>100110 - Disclosure - Other Comprehensive Income (Loss)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureOtherComprehensiveIncomeLoss</Role>
      <ShortName>Other Comprehensive Income (Loss)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>100120 - Disclosure - Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureLeases</Role>
      <ShortName>Leases</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>100130 - Disclosure - Description of Business and Summary of Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureDescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Description of Business and Summary of Significant Accounting Policies (Policies)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>100140 - Disclosure - Inventory (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureInventoryTables</Role>
      <ShortName>Inventory (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>100150 - Disclosure - Share-based Compensation Expense (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureShareBasedCompensationExpenseTables</Role>
      <ShortName>Share-based Compensation Expense (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>100160 - Disclosure - Other Comprehensive Income (Loss) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureOtherComprehensiveIncomeLossTables</Role>
      <ShortName>Other Comprehensive Income (Loss) (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>100170 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureDescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail</Role>
      <ShortName>Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>100180 - Disclosure - Components of Inventories (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureComponentsOfInventoriesDetail</Role>
      <ShortName>Components of Inventories (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>100190 - Disclosure - Long-term Debt - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail</Role>
      <ShortName>Long-term Debt - Additional Information (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>100200 - Disclosure - Legal Proceedings - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureLegalProceedingsAdditionalInformationDetail</Role>
      <ShortName>Legal Proceedings - Additional Information (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>100210 - Disclosure - Summary of Share-Based Compensation Expense (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureSummaryOfShareBasedCompensationExpenseDetail</Role>
      <ShortName>Summary of Share-Based Compensation Expense (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>100220 - Disclosure - Share-Based Compensation Expense by Types of Awards (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureShareBasedCompensationExpenseByTypesOfAwardsDetail</Role>
      <ShortName>Share-Based Compensation Expense by Types of Awards (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>100230 - Disclosure - Total Accumulated Other Comprehensive Income (Loss) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureTotalAccumulatedOtherComprehensiveIncomeLossDetail</Role>
      <ShortName>Total Accumulated Other Comprehensive Income (Loss) (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>100240 - Disclosure - Leases - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.ctibiopharma.com/20140630/taxonomy/role/DisclosureLeasesAdditionalInformationDetail</Role>
      <ShortName>Leases - Additional Information (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs>
    <Log type="Info">Element us-gaap_DerivativeLiabilitiesCurrent had a mix of decimals attribute values: -5 -3.</Log>
    <Log type="Info">'Monetary' elements on report '100190 - Disclosure - Long-term Debt - Additional Information (Detail)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">Process Flow-Through: 100010 - Statement - Condensed Consolidated Balance Sheets (Unaudited)</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Jun. 30, 2013'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2012'</Log>
    <Log type="Info">Process Flow-Through: 100020 - Statement - Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 100030 - Statement - Condensed Consolidated Statements of Operations (Unaudited)</Log>
    <Log type="Info">Process Flow-Through: 100040 - Statement - Condensed Consolidated Statements of Comprehensive Loss (Unaudited)</Log>
    <Log type="Info">Process Flow-Through: 100050 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited)</Log>
  </Logs>
  <InputFiles>
    <File>ctic-20140630.xml</File>
    <File>ctic-20140630.xsd</File>
    <File>ctic-20140630_cal.xml</File>
    <File>ctic-20140630_def.xml</File>
    <File>ctic-20140630_lab.xml</File>
    <File>ctic-20140630_pre.xml</File>
  </InputFiles>
  <SupplementalFiles />
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
