Counter-security paid to the Korean courts for the purpose of lifting the arrest of a vessel.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of damages suffered and related expenses incurred by the Company.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The percentage of the purchase price of the vessel being sold under a Memorandum of Agreement that the buyers were required to deposit into an escrow account administered by the escrow agent as security for completion of the transaction.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Period of time after arbitrator issued an award to the owners for buyers of vessel to file an appeal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	ctrm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Cash received for the counter-security payment and gross interest earned on the deposit.

+ References

No definition available.

+ Details

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Namespace Prefix:	ctrm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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

- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-1

+ Details

Name:	us-gaap_LossContingencyAccrualProvision
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Cash received for the settlement of litigation during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 25
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-25

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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

- Details

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Namespace Prefix:
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- Details

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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Commitments and Contingencies, Claims and Contingencies (Details) - USD ($)				12 Months Ended
	Oct. 04, 2024	May 28, 2024	Mar. 23, 2023	Dec. 31, 2024	Dec. 31, 2023
Sale of M/V Magic Moon [Member]
Claims and Continengies [Abstract]
Percentage of purchase price required as deposit into escrow account			10.00%
Deposit into escrow by buyers			$ 1,395,000
Period to file appeal after award by arbitrator				28 days
Proceeds from a claim		$ 1,411,356
Collection of counter-security payment and interest	$ 1,401,740
Sale of M/V Magic Moon [Member] \| Prepaid Expenses and Other Assets [Member]
Claims and Continengies [Abstract]
Damages and related expenses				$ 115,000	$ 115,000
Counter-security payment					$ 1,395,000
Various Circumstances Involving Uncertainty [Member]
Claims and Continengies [Abstract]
Provision recognized for possible losses				3,800,000
Potential Prospectus Errors for Closed-end Funds [Member]
Claims and Continengies [Abstract]
Provision recognized for possible losses				1,100,000
Contingent Liabilities for Potential Prospectus Errors for Closed-end Funds [Member]
Claims and Continengies [Abstract]
Provision recognized for possible losses				$ 2,400,000