XML 52 R35.htm IDEA: XBRL DOCUMENT
v3.20.2

Financial Condition and Business Plan (Details Narrative) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2020 | Apr. 30, 2020 | Jun. 30, 2018 | Dec. 31, 2019 | Dec. 31, 2018
Cumulated net losses | $ (300,916,593) |  |  | $ (290,516,780) |
Cash, investment securities and interest receivable | 25,500,000 |  |  |  |
Horizon Credit Agreement [Member] | Horizon Technology Finance Corporation [Member] |  |  |  |  |
Proceeds from new capital |  |  | $ 10,000,000 |  |
Horizon Credit Agreement [Member] | Horizon Technology Finance Corporation [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |
Debt instrument, interest rate |  |  | 7.625% |  |
New Jersey [Member] |  |  |  |  |
Tax benefits of EDA |  |  |  | 1,900,000 | $ 10,400,000
Net proceeds from sale of net operating losses | $ 2,000,000 | $ 1,800,000 |  | $ 1,800,000 | $ 11,100,000

X
- Definition The amount of cash, investment securities and interest receivable. + References No definition available. + Details
Name: | CLSN_CashInvestmentSecuritiesAndInterestReceivable
Namespace Prefix: | CLSN_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Net proceeds from sale of net operating losses + References No definition available. + Details
Name: | CLSN_NetProceedsFromSaleOfNetOperatingLosses
Namespace Prefix: | CLSN_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Tax benefits of EDA + References No definition available. + Details
Name: | CLSN_TaxBenefitsOfEarningsBeforeDepreciationAndAmortization
Namespace Prefix: | CLSN_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash inflow associated with the amount received by a corporation from a shareholder during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromContributedCapital
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(30)(a)(3)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (g)(2) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(a)(4)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(2)(i) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 + Details
Name: | us-gaap_RetainedEarningsAccumulatedDeficit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=CLSN_HorizonCreditAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=CLSN_HorizonTechnologyFinanceCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=CLSN_NJMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |