v3.25.3

Deferred compensation - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Deferred compensation
Description of deferred compensation arrangements			The Mayville Engineering Company Deferred Compensation Plan is available for certain employees designated to be eligible to participate by the Company and approved by the Board of Directors.
Deferred compensation arrangements, awards granted percentage			50.00%
Annual short term cash incentive percentage			100.00%
Deferred compensation cash-based arrangements liability, Current	$ 1,397		$ 1,397		$ 251
Deferred compensation cash-based arrangements liability, Non current	4,672		4,672		$ 4,719
Deferred compensation plan (Income) expense	2,221	$ 2,076	7,071	$ 10,010
Deferred compensation, distributions paid			253	286
Deferred Profit Sharing
Deferred compensation
Deferred compensation plan (Income) expense	281	204	591	489
Employees
Deferred compensation
Amount of compensation deferred	$ 87	$ 96	$ 762	$ 544

The amount of compensation deferred during the period pertaining to the deferred compensation arrangement.

+ References

No definition available.

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- Definition

Deferred compensation arrangement with individual annual short term cash incentive percentage.

+ References

No definition available.

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- Definition

Commitment made to pay deferred cash remuneration expressed as a percentage of the individual's base salary.

+ References

No definition available.

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- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 710
-SubTopic 10
-Name Accounting Standards Codification
-Section 30
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483043/710-10-30-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-1

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- Definition

Description of the deferred compensation arrangement, including fixed amounts and determinable awards, or the method for determining payments and awards, the timing of such payments and awards, and any requisite service or performance criteria, as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 55
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482943/710-10-55-7

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-1

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- Definition

Amount of distribution made to individual in accordance with deferred compensation arrangement.

+ References

No definition available.

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- 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.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for deferred compensation arrangements payable within one year (or the normal operating cycle, if longer). Represents currently earned compensation under cash arrangements (such as a profit-sharing plan, rabbi trust, and employee contract--excluding equity-based arrangements) that is not actually paid until a later date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483043/710-10-30-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 25
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483070/710-10-25-15

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for deferred compensation arrangements payable after one year (or the normal operating cycle, if longer). Represents currently earned compensation under cash arrangements (such as a profit-sharing plan, rabbi trust, and employee contract--excluding equity-based arrangements) that is not actually paid until a later date.

+ References

No definition available.

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Mayville Engineering Company, Inc. 10-Q