v3.26.1
Description of Plan - Contributions (Details) - Mayville Engineering Company, Inc. 401(k) Plan
12 Months Ended
Dec. 31, 2025
USD ($)
item
Y
Description of Plan  
Minimum service period for profit sharing contribution eligibility (in hours) | item 1,000
Participant's contribution 50.00%
Age for contribution eligibility | Y 50
Deferral rate 4.00%
Auto-escalation of contribution rates 1.00%
Matching contributions 50.00%
Percentage of matching contribution 6.00%
Discretionary contributions | $ $ 0
Maximum  
Description of Plan  
Auto-escalation of contribution rates 6.00%