Earnings (Loss) per Share - Outstanding Common Stock Equivalents Excluded from Computation of Diluted Earnings (Loss) per Share (Details) - shares	3 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Earnings Per Share [Abstract]
Stock-based awards (in shares)	5,000,074	8,611,063

Common Stock Equivalents Excluded From Computation Of Earnings Per Share, Amount

No definition available.

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Namespace Prefix:	mh_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration