Commercial surety bonding capacity maximum limit.

No definition available.

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

- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

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

- Definition

Indicates status and type of related party for accounts payable classified as current.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Indicates status and type of related party for receivable, after allowance for credit loss, classified as other.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount due from parties in nontrade transactions, classified as other.

+ References

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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Topic 235
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+ Details

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

- Definition

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Period Type:

Related Party Transactions - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Related Party \| Commercial surety bond facility
Related Party Transaction [Line Items]
Commercial surety bonding capacity maximum limit	$ 30,000		$ 30,000
MPR - logging JV
Related Party Transaction [Line Items]
Ownership percentage	20.00%		20.00%
Related party transaction, purchases from related party	$ 596	$ 805	$ 2,991	$ 3,774
Related party payable balance	$ 19		$ 19
Accounts Payable, Current, Related Party [Extensible Enumeration]	Related Party		Related Party
Related party receivable balance					$ 1,077
Other Receivable, after Allowance for Credit Loss, Related Party [Extensible Enumeration]					Related Party
PLWD - Wood Purchasing
Related Party Transaction [Line Items]
Ownership percentage	26.00%		26.00%
Related party transaction, purchases from related party	$ 3,939	$ 3,434	$ 5,292	$ 5,662
Related party payable balance	$ 154		$ 154		$ 0
Accounts Payable, Current, Related Party [Extensible Enumeration]	Related Party		Related Party		Related Party