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

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Trailing period to maintain earnings before interest, taxes, depreciation, and amortization (EBITDA) to net interest expense ratio above a certain level in the debt agreement, 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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- Definition

Number of the Company's subsidiaries that provided security for a senior secured term loan facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	ctrm_
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Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- 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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Long-Term Debt, $55.0 Million Term Loan Facility (Details) - $55.0 Million Term Loan Facility [Member]		12 Months Ended
	Jan. 13, 2022 USD ($) Tranches	Dec. 31, 2022 USD ($) Installment	Jan. 12, 2022 Subsidiary
Long-Term Debt [Abstract]
Face amount	$ 55,000,000	$ 55,000,000
Number of subsidiaries providing security for term loan facility \| Subsidiary			5
Number of tranches drawn \| Tranches	5
Term of loan		5 years
Number of payment installments \| Installment		20
Frequency of periodic payment		quarterly
Balloon installment payable at maturity		$ 12,570,000
Trailing period to maintain EBITDA to net interest expense ratio		12 months
SOFR [Member]
Long-Term Debt [Abstract]
Margin on variable rate		3.15%
Installments 1 to 6 [Member]
Long-Term Debt [Abstract]
Installment payment		$ 3,535,000
Installments 7 to 12 [Member]
Long-Term Debt [Abstract]
Installment payment		1,750,000
Installments 13 to 20 [Member]
Long-Term Debt [Abstract]
Installment payment		$ 1,340,000