Share Repurchase Program (Details) - Common Stock [Member]	6 Months Ended
Sep. 30, 2018 USD ($) shares
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, approved amount	$ 37,000,000
Shares utilized, amount	15,692,000
Shares available for repurchase, amount	$ 21,308,000
Shares repurchased and retired (in shares) \| shares	675,561

The cumulative equity impact of the value of stock that has been repurchased and retired since the inception of the repurchase program. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

No definition available.

Name:	mpaa_StockRepurchasedAndRetiredDuringPeriodCumulativeValue
Namespace Prefix:	mpaa_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration