Change in fair value of investments.

No definition available.

Name:	MRMD_ChangeInFairValueOfInvestments
Namespace Prefix:	MRMD_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Membership interest transferred, percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	MRMD_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The difference between the carrying value and the sale price of equity securities, not separately or otherwise categorized as trading or available-for-sale. This element includes investments in which the entity holds a small ownership stake (generally, less than 20% of the shares outstanding) and cannot exert significant influence.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(h))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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Balance Type:	debit
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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Topic 505
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Details

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- Details

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INVESTMENTS (Details Narrative) - USD ($)	1 Months Ended			6 Months Ended
INVESTMENTS (Details Narrative) - USD ($)	Jan. 31, 2021	Dec. 31, 2020	Aug. 31, 2018	Jun. 30, 2021	Jun. 30, 2020
Acquired Indefinite-lived Intangible Assets [Line Items]
Investments		$ 2,522,981		$ 2,107,698
Number of common stock issued, value
MembersRSVP LLC [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Investments			$ 300,000
Number of common stock issued during period			378,259
Number of common stock issued, value			$ 915,000
Ownership percentage	12.00%		23.00%
Gain (Loss) on Sale of Equity Investments					33,000
Membership interest transferred	11.00%
Flowr Corp. (Formerly Terrace Inc.) [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Percentage for acquired interest rate		8.95%
Number of shares received under acquisition		0.4973
Change in fair value of investments				$ 415,000	$ 664,000