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Minimum value of shares and/or other securities issued by an entity engaged in the maritime industry upon which the Company would be required to pay a commission if such shares and/or other securities are acquired or sold.

No definition available.

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The number of vessels acquired by the entity during the period.

No definition available.

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The number of vessels sold by the entity during the period.

No definition available.

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The percentage of the gross charter hire, freight and the ballast bonus earned under a charter charged as a commission to the Company by a related party.

No definition available.

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A commission rate charged by a related party on each consummated transaction applicable to the total consideration of acquiring or selling: (a) a vessel or (b) the shares of a ship owning entity owning vessel(s) or (c) shares and/or other securities with an aggregate purchase or sale value, as the case may be, of an amount equal to, or in excess of, $10,000,000 issued by an entity engaged in the maritime industry.

No definition available.

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Commissions paid to a related party broker on time-charter and voyage-charter arrangements.

No definition available.

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- References

No definition available.

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Fixed daily fee charged by a related party to provide a wide range of shipping services such as crew management, technical management, operational employment management, insurance arrangements, provisioning, bunkering, accounting services, general administration and audit support.

No definition available.

Name:	ctrm_RelatedPartyTransactionFixedDailyFee
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Data Type:	srt-types:perUnitItemType
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Flat quarterly management fee paid to related party for the management and administration of the Company's business.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Fees paid to related parties for providing a wide range of shipping services such as crew management, technical management, operational employment management, insurance arrangements, provisioning, bunkering, accounting services, general administration and audit support.

No definition available.

Name:	ctrm_RelatedPartyTransactionManagementFees
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Recovery fee multiplier applied to the total amount of the flat management fee calculated on an annual basis under an agreement with a related party.

No definition available.

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Termination fee multiplier applied to the total amount of the flat management fee and the per vessel management fee calculated on an annual basis under an agreement with a related party.

No definition available.

Name:	ctrm_RelatedPartyTransactionManagementTerminationFeeMultiplier
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Data Type:	xbrli:pureItemType
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Fixed quarterly fee charged by a related party to provide a shipping related administrative services.

No definition available.

Name:	ctrm_RelatedPartyTransactionQuarterlyManagementFee
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Term of related party agreement renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

No definition available.

Name:	ctrm_RelatedPartyTransactionRenewalTermOfAgreement
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Data Type:	xbrli:durationItemType
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Amount of commissions charged by related party on each consummated transaction applicable to the total consideration of acquiring or selling: (a) a vessel or (b) the shares of a ship owning entity owning vessel(s) or (c) shares and/or other securities with an aggregate purchase or sale value, as the case may be, of an amount equal to, or in excess of $10,000,000 issued by an entity engaged in the maritime industry.

No definition available.

Name:	ctrm_RelatedPartyTransactionSaleAndPurchaseCommissions
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Balance Type:	debit
Period Type:	duration

Term of related party agreement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

No definition available.

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

Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
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-Name Accounting Standards Codification
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Amount, after allowance for credit loss, of receivable classified as other and noncurrent.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
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Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

No definition available.

Name:	us-gaap_OtherReceivablesNetCurrent
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