Note 4 - Balance Sheet Components (Details Textual) - USD ($) $ in Thousands	Mar. 31, 2023	Jan. 01, 2023	Dec. 31, 2022
Prepaid Wafer Purchase	$ 50,000	$ 50,000	$ 0
Inventory, Stock Rotation Reserve	$ 26,400		$ 14,300

Amount of prepaid wafer purchase, classified as current.

No definition available.

Name:	mpwr_PrepaidWaferPurchaseCurrent
Namespace Prefix:	mpwr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant