VARIABLE INTEREST ENTITIES (Details) - Variable Interest Entity, Primary Beneficiary [Member]	Sep. 30, 2024 USD ($) Entity	Jun. 30, 2024 USD ($) Entity
Nonconsolidated Variable Interest Entities [Abstract]
Number of unconsolidated VIEs \| Entity	2	2
Total Nonconsolidated VIEs [Abstract]
Fair value of investments in VIEs	$ 773,001	$ 796,940
Carrying value of variable interests - assets	867,358	867,358
Maximum Exposure to Loss [Abstract]
Limited Partnership Interest	$ 867,358	$ 867,358

No definition available.

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- Definition

The number of unconsolidated variable interest entities in limited partnerships and limited liability companies.

+ References

No definition available.

+ Details

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- Definition

Fair value of the investment in variable interest entities at close of period.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), when the reporting entity is not the VIE's primary beneficiary.

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No definition available.

+ Details

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Namespace Prefix:	mrc_
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Balance Type:	debit
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- References

No definition available.

+ Details

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481203/810-10-50-6

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 810
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481203/810-10-50-4

+ Details

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Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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- Details

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