Insider Trading Arrangements	3 Months Ended	6 Months Ended
Insider Trading Arrangements	Jun. 30, 2025	Jun. 30, 2025
Trading Arrangements, by Individual [Table]
Material Terms of Trading Arrangement [Text Block]		Item 5. Other Information Certain of our executive officers and directors have entered into trading plans pursuant to Rule 10b5-1(c) of the Securities Exchange Act of 1934, as amended. A trading plan is a written document that pre-establishes the amounts, prices and dates (or formula for determining the amounts, prices and dates) of future purchases or sales of our common stock, including the sale of shares acquired pursuant to the Monolithic Power Systems, Inc. 2004 Employee Stock Purchase Plan, amended and restated, and upon vesting of RSUs. During the three months ended June 30, 2025, no trading plans intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) were adopted, modified, or terminated, and no other written trading arrangements that are not intended to qualify for the Rule 10b5-1(c) affirmative defense were adopted, modified, or terminated.
Non-Rule 10b5-1 Arrangement Adopted [Flag]	false
Non-Rule 10b5-1 Arrangement Terminated [Flag]	false
Rule 10b5-1 Arrangement Adopted [Flag]	false
Rule 10b5-1 Arrangement Terminated [Flag]	false

MONOLITHIC POWER SYSTEMS INC 10-Q