Commitments and Contingencies, Claims (Details) - USD ($)		12 Months Ended
Mar. 23, 2023	Dec. 31, 2023
Minimum [Member]
Claims [Abstract]
Period before arbitrator is expected to issue award		45 days
Maximum [Member]
Claims [Abstract]
Period before arbitrator is expected to issue award		60 days
Sale of M/V Magic Moon [Member]
Claims [Abstract]
Percentage of purchase price required as deposit into escrow account	10.00%
Deposit into escrow by buyers	$ 1,395,000
Sale of M/V Magic Moon [Member] \| Prepaid Expenses and Other Assets [Member]
Claims [Abstract]
Damages and related expenses		$ 115,000
Counter-security payment		$ 1,395,000

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

No definition available.

Name:	ctrm_CounterSecurityPayment
Namespace Prefix:	ctrm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	ctrm_LossContingencyDamagesAndRelatedExpenses
Namespace Prefix:	ctrm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

Name:	ctrm_PercentageOfPurchasePriceRequiredAsDepositIntoEscrowAccount
Namespace Prefix:	ctrm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time before arbitrator is expected to issue an award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	ctrm_PeriodBeforeArbitratorIsToIssueAward
Namespace Prefix:	ctrm_
Data Type:	xbrli:durationItemType
Balance Type:	na
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

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

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

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=ctrm_SaleOfMVMagicMoonMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: