Deferred charges, net (Details)	6 Months Ended
Jun. 30, 2022 USD ($)
Deferred charges, net [Abstract]
Balance at beginning of period	$ 4,862,824
Additions	1,878,818
Less: Insurance claim recognized	(550,000)
Amortization	(880,144)
Balance at end of period	$ 5,311,498

Amount of additions to asset recognized from cost incurred to obtain or fulfill contract with customer.

No definition available.

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

- Definition

Amount of insurance claim recognized related to asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

No definition available.

+ Details

Name:	ctrm_CapitalizedContractCostInsuranceClaimRecognized
Namespace Prefix:	ctrm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126905575&loc=SL49131252-203054

+ Details

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

- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126905575&loc=SL49131252-203054

+ Details

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

- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration