The number of periodic payment installments in which the debt is to be repaid.

No definition available.

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

- Definition

The number of tranches in which the debt instrument was drawn down.

+ References

No definition available.

+ Details

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Namespace Prefix:	ctrm_
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- Definition

Number of the Company's ship-owning subsidiaries that entered into a senior secured term loan facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	ctrm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

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Balance Type:	na
Period Type:	duration

- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

+ Details

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

- Definition

Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

+ References

No definition available.

+ Details

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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- Details

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- Details

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Long-Term Debt, $18.0 million Term Loan Facility (Details) - $18.0 Million Term Loan Facility [Member]		12 Months Ended
	May 07, 2021 Tranche	Dec. 31, 2021 USD ($) Installment	Apr. 27, 2021 USD ($) Subsidiary
Long-Term Debt [Abstract]
Number of ship-owning subsidiaries entering into term loan facility \| Subsidiary			2
Face amount		$ 18,000,000.0	$ 18,000,000.0
Number of tranches drawn \| Tranche	2
Term of loan		4 years
Number of payment installments \| Installment		16
Frequency of periodic payment		quarterly
Balloon installment payable at maturity		$ 6,500,000
Quarterly Installments 1 to 4 [Member]
Long-Term Debt [Abstract]
Installment payment		850,000
Quarterly Installments 5 to 16 [Member]
Long-Term Debt [Abstract]
Installment payment		$ 675,000