Name:	icon_DebtInstrumentBorrowingCapacity
Namespace Prefix:	icon_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Minimum ratio of loan to mortgaged value required by debt covenants.

No definition available.

Name:	icon_DebtInstrumentCovenantMinimumLoanToMortgagedVesselsValueRatio
Namespace Prefix:	icon_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Minimum restricted cash deposits per mortgaged vessel to be maintained by the Company.

No definition available.

Name:	icon_DebtInstrumentCovenantMinimumRestrictedCashDeposits
Namespace Prefix:	icon_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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

- References

No definition available.

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

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14