XML 89 R66.htm IDEA: XBRL DOCUMENT v3.22.4

LEASES - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) renewalOption	Dec. 31, 2021 USD ($)
Lessee, Lease, Description [Line Items]
Initial term	91 months
Number of renewal options | renewalOption	1
Renewal options term	5 years
Annual base rent	$ 1.2
Tenant improvement allowance	1.8
Prepaid rent	$ 0.6	$ 0.2
Minimum
Lessee, Lease, Description [Line Items]
Lease terms	1 month
Lease renewal terms	1 year
Maximum
Lessee, Lease, Description [Line Items]
Lease terms	5 years
Lease renewal terms	5 years

X

- Definition

Annual Base Rent

+ References

No definition available.

+ Details

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

X

- Definition

Lessee, Operating Lease, Number Of Renewal Options

+ References

No definition available.

+ Details

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

X

- Definition

Lessee, Renewal Term

+ References

No definition available.

+ Details

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Namespace Prefix:	mp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Lessee, Term Of Contract

+ References

No definition available.

+ Details

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Namespace Prefix:	mp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tenant Improvement Allowance

+ References

No definition available.

+ Details

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Namespace Prefix:	mp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

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

X

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918673-209980

+ Details

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

X

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918673-209980

+ Details

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

X

- Definition

Amount of asset related to consideration paid in advance for rent that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 10
-Section 05
-Paragraph 5
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126905020&loc=d3e5879-108316

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 10
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6387103&loc=d3e6435-108320

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (g)(3)
-URI https://asc.fasb.org/extlink&oid=124098289&loc=d3e6676-107765

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	instant

X

- Details

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