$MPWR
Monolithic Power Systems Inc Stock $mpwr

$mpwr Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000143774921004587 Filed on March 01, 2021

Income Statement

Concept	2019 Q4	2018	2017 Q4
Revenue	$166.7M	$582.4M	$129.4M
YoY Change	8.63%	23.67%	24.91%
Cost Of Revenue	$74.80M	$259.7M	$58.27M
YoY Change	8.56%	22.13%	23.69%
Gross Profit	$91.94M	$322.7M	$71.16M
YoY Change	8.68%	24.93%	25.92%
Gross Profit Margin	55.14%	55.4%	54.98%
Selling, General & Admin	$33.24M	$113.8M	$24.04M
YoY Change	17.16%	17.01%	12.77%
% of Gross Profit	36.16%	35.27%	33.78%
Research & Development	$27.01M	$93.46M	$21.73M
YoY Change	18.81%	13.47%	20.9%
% of Gross Profit	29.38%	28.96%	30.54%
Depreciation & Amortization	$4.100M	$12.31M	$4.000M
YoY Change	28.12%	-23.54%	-4.76%
% of Gross Profit	4.46%	3.82%	5.62%
Operating Expenses	$61.24M	$209.2M	$46.11M
YoY Change	18.88%	15.66%	18.32%
Operating Profit	$30.69M	$113.5M	$25.05M
YoY Change	-7.2%	46.58%	42.82%
Interest Expense	$1.700M	$6.321M	$1.300M
YoY Change	-5.56%	18.08%	44.44%
% of Operating Profit	5.54%	5.57%	5.19%
Other Income/Expense, Net	$2.731M	$4.994M	$1.647M
YoY Change	-794.91%	-9.53%	83.61%
Pretax Income	$33.43M	$118.5M	$26.70M
YoY Change	2.27%	42.85%	44.8%
Income Tax	$989.0K	$13.21M	$14.63M
% Of Pretax Income	2.96%	11.15%	54.79%
Net Earnings	$32.44M	$105.3M	$12.07M
YoY Change	17.36%	61.45%	-27.16%
Net Earnings / Revenue	19.45%	18.08%	9.33%
Basic Earnings Per Share	$0.75	$2.49	$0.29
Diluted Earnings Per Share	$0.70	$2.36	$0.27
COMMON SHARES
Basic Shares Outstanding	43.44M	42.25M
Diluted Shares Outstanding	46.50M	44.60M	44.61M

Balance Sheet

Concept	2019 Q4	2018	2017 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$455.4M	$377.3M	$299.1M
YoY Change	20.7%	26.15%	11.52%
Cash & Equivalents	$173.0M	$172.7M	$82.76M
Short-Term Investments	$282.4M	$204.6M	$216.3M
Other Short-Term Assets	$19.61M	$5.700M	$12.76M
YoY Change	64.32%	-44.12%	41.13%
Inventory	$127.5M	$136.4M	$99.28M
Prepaid Expenses	$7.991M
Receivables	$52.70M	$55.20M	$38.04M
Other Receivables	$8.600M	$6.200M	$1.400M
Total Short-Term Assets	$655.2M	$580.8M	$449.2M
YoY Change	12.81%	29.3%	17.28%
LONG-TERM ASSETS
Property, Plant & Equipment	$228.3M	$150.0M	$144.6M
YoY Change	52.21%	3.73%	69.82%
Goodwill	$6.571M		$6.571M
YoY Change	0.0%		0.0%
Intangibles			$951.0K
YoY Change			-68.32%
Long-Term Investments	$3.100M	$3.200M	$5.300M
YoY Change	-3.13%	-39.62%	-1.85%
Other Assets	$49.09M	$52.70M	$30.07M
YoY Change	36.44%	14.57%	9.69%
Total Long-Term Assets	$301.2M	$212.6M	$203.4M
YoY Change	41.65%	4.52%	58.73%
TOTAL ASSETS
Total Short-Term Assets	$655.2M	$580.8M	$449.2M
Total Long-Term Assets	$301.2M	$212.6M	$203.4M
Total Assets	$956.4M	$793.4M	$652.6M
YoY Change	20.54%	21.58%	27.67%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$27.27M	$22.70M	$22.81M
YoY Change	20.25%	-0.44%	30.91%
Accrued Expenses	$44.79M	$33.20M	$27.51M
YoY Change	14.96%	36.07%	20.03%
Deferred Revenue	$3.412M		$4.742M
YoY Change	35.4%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$98.23M	$80.40M	$65.92M
YoY Change	22.11%	22.0%	24.56%
LONG-TERM LIABILITIES
Long-Term Debt	$0.00	$0.00	$0.00
YoY Change
Other Long-Term Liabilities	$47.06M	$38.50M	$33.02M
YoY Change	22.16%	16.67%	42.23%
Total Long-Term Liabilities	$47.06M	$38.50M	$33.02M
YoY Change	22.16%	16.67%	42.23%
TOTAL LIABILITIES
Total Short-Term Liabilities	$98.23M	$80.40M	$65.92M
Total Long-Term Liabilities	$47.06M	$38.50M	$33.02M
Total Liabilities	$182.9M	$153.3M	$130.6M
YoY Change	19.27%	17.38%	63.18%
SHAREHOLDERS EQUITY
Retained Earnings	$229.5M		$143.6M
YoY Change	17.83%		20.31%
Common Stock
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$773.5M	$640.1M	$522.0M
YoY Change
Total Liabilities & Shareholders Equity	$956.4M	$793.4M	$652.6M
YoY Change	20.54%	21.58%	27.67%

Cashflow Statement

Concept	2019 Q4	2018	2017 Q4
OPERATING ACTIVITIES
Net Income	$32.44M	$105.3M	$12.07M
YoY Change	17.36%	61.45%	-27.16%
Depreciation, Depletion And Amortization	$4.100M	$12.31M	$4.000M
YoY Change	28.12%	-23.54%	-4.76%
Cash From Operating Activities	$61.00M	$141.5M	$53.40M
YoY Change	28.15%	5.7%	72.26%
INVESTING ACTIVITIES
Capital Expenditures	-$8.700M	$22.53M	-$40.70M
YoY Change	97.73%	-65.75%	402.47%
Acquisitions
YoY Change
Other Investing Activities	-$70.30M	$7.800M	-$25.60M
YoY Change	-711.3%	-111.42%	156.0%
Cash From Investing Activities	-$79.00M	-$14.74M	-$66.30M
YoY Change	-1212.68%	-89.0%	268.33%
FINANCING ACTIVITIES
Cash Dividend Paid		$47.48M
YoY Change		39.94%
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-17.10M	-$34.56M	-8.600M
YoY Change	32.56%	10.32%	7.5%
NET CHANGE
Cash From Operating Activities	61.00M	$141.5M	53.40M
Cash From Investing Activities	-79.00M	-$14.74M	-66.30M
Cash From Financing Activities	-17.10M	-$34.56M	-8.600M
Net Change In Cash	-35.10M	$89.94M	-21.50M
YoY Change	-183.97%	-384.96%	-530.0%
FREE CASH FLOW
Cash From Operating Activities	$61.00M	$141.5M	$53.40M
Capital Expenditures	-$8.700M	$22.53M	-$40.70M
Free Cash Flow	$69.70M	$118.9M	$94.10M
YoY Change	34.04%	74.76%	140.66%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	150000000
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	150000000
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CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	43616000
CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	43616000
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	325000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	203000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	-209000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.20
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.60
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.00
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	0	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	0	USD
CY2020	us-gaap	Other Than Temporary Impairment Loss Debt Securities Available For Sale OtherThanTemporaryImpairmentLossDebtSecuritiesAvailableForSale	0	USD
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CY2020	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	0	USD
CY2019	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	0	USD
CY2018	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	0	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	334944000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	172960000	USD
CY2020Q4	us-gaap	Short Term Investments ShortTermInvestments	260169000	USD
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CY2020Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	66843000	USD
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CY2020Q4	us-gaap	Inventory Net InventoryNet	157062000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	127500000	USD
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CY2019Q4	us-gaap	Other Assets Current OtherAssetsCurrent	19605000	USD
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CY2019Q4	us-gaap	Assets Current AssetsCurrent	655206000	USD
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CY2020Q4	us-gaap	Goodwill Goodwill	6571000	USD
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CY2018	us-gaap	Gross Profit GrossProfit	322668000	USD
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CY2020	mpwr	Litigation Expense Benefit Net LitigationExpenseBenefitNet	7804000	USD
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CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-729000	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-1353000	USD
CY2020	mpwr	Gain Loss On Deferred Compensation Plan Investments Cash Flow GainLossOnDeferredCompensationPlanInvestmentsCashFlow	4592000	USD
CY2019	mpwr	Gain Loss On Deferred Compensation Plan Investments Cash Flow GainLossOnDeferredCompensationPlanInvestmentsCashFlow	3806000	USD
CY2018	mpwr	Gain Loss On Deferred Compensation Plan Investments Cash Flow GainLossOnDeferredCompensationPlanInvestmentsCashFlow	-255000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1627000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-577000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-843000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	85551000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	78699000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	60607000	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	1072000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	259000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-22000	USD
CY2020	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	14123000	USD
CY2019	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-2512000	USD
CY2018	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	18079000	USD
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	29503000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-8865000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	37060000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	3003000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	10204000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	1075000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	10410000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	3048000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	871000	USD
CY2020	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	18524000	USD
CY2019	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	7496000	USD
CY2018	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	3806000	USD
CY2020	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	747000	USD
CY2019	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-1355000	USD
CY2018	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	6923000	USD
CY2020	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	19951000	USD
CY2019	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	7449000	USD
CY2018	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	7092000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	267803000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	216303000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	141451000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	55639000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	95806000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	22526000	USD
CY2020	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	29000	USD
CY2019	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	9268000	USD
CY2018	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2020	mpwr	Payments To Acquire In Place Leases PaymentsToAcquireInPlaceLeases	-0	USD
CY2019	mpwr	Payments To Acquire In Place Leases PaymentsToAcquireInPlaceLeases	981000	USD
CY2018	mpwr	Payments To Acquire In Place Leases PaymentsToAcquireInPlaceLeases	-0	USD
CY2020	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	334947000	USD
CY2019	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	212562000	USD
CY2018	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	99199000	USD
CY2020	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	357092000	USD
CY2019	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	135801000	USD
CY2018	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	109131000	USD
CY2020	us-gaap	Payments To Acquire Longterm Investments PaymentsToAcquireLongtermInvestments	3316000	USD
CY2019	us-gaap	Payments To Acquire Longterm Investments PaymentsToAcquireLongtermInvestments	-0	USD
CY2018	us-gaap	Payments To Acquire Longterm Investments PaymentsToAcquireLongtermInvestments	-0	USD
CY2020	us-gaap	Proceeds From Sale Of Longterm Investments ProceedsFromSaleOfLongtermInvestments	300000	USD
CY2019	us-gaap	Proceeds From Sale Of Longterm Investments ProceedsFromSaleOfLongtermInvestments	250000	USD
CY2018	us-gaap	Proceeds From Sale Of Longterm Investments ProceedsFromSaleOfLongtermInvestments	2000000	USD
CY2020	mpwr	Contributions Made To Deferred Compensation Plan ContributionsMadeToDeferredCompensationPlan	2696000	USD
CY2019	mpwr	Contributions Made To Deferred Compensation Plan ContributionsMadeToDeferredCompensationPlan	3082000	USD
CY2018	mpwr	Contributions Made To Deferred Compensation Plan ContributionsMadeToDeferredCompensationPlan	4146000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-39177000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-167112000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-14740000	USD
CY2020	mpwr	Property And Equipment Purchased On Extended Payment Terms PropertyAndEquipmentPurchasedOnExtendedPaymentTerms	5357000	USD
CY2019	mpwr	Property And Equipment Purchased On Extended Payment Terms PropertyAndEquipmentPurchasedOnExtendedPaymentTerms	683000	USD
CY2018	mpwr	Property And Equipment Purchased On Extended Payment Terms PropertyAndEquipmentPurchasedOnExtendedPaymentTerms	749000	USD
CY2020	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	18767000	USD
CY2019	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	16650000	USD
CY2018	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	10637000	USD
CY2020	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	3819000	USD
CY2019	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	3277000	USD
CY2018	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	3028000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	88786000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	67294000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	47475000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-71557000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-48050000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-34559000	USD
CY2020	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	4926000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-883000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-2208000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	161995000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	258000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	89944000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	173076000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	172818000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	82874000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	335071000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	173076000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	172818000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1405000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	10700000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	7134000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	7839000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	7803000	USD
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	1737000	USD
CY2020Q4	mpwr	Dividends And Dividend Equivalents Accrued DividendsAndDividendEquivalentsAccrued	27507000	USD
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"><b><i>Prior Period Reclassifications</i></b></p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"> </p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;">Certain amounts in prior periods have been reclassified to conform with current period presentation:</p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"> </p> <table border="0" cellpadding="0" cellspacing="0" style="width: 100%; text-indent: 0px;"><tbody><tr style="vertical-align: top;"><td style="width: 18pt;"> </td><td style="width: 18pt;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;">●</p> </td><td> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;">Long-term investments, which were previously presented separately on the Consolidated Balance Sheets, are now reported within other long-term assets.</p> </td></tr> </tbody></table> <table border="0" cellpadding="0" cellspacing="0" style="width: 100%; text-indent: 0px;"><tbody><tr style="vertical-align: top;"><td style="width: 18pt;"> </td><td style="width: 18pt;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;">●</p> </td><td style="font-family: "Times New Roman"; font-size: 10pt;">Gains and losses on the disposal and sale of property and equipment, which were previously presented separately under operating activities on the Consolidated Statements of Cash Flows, are now reported within the “other” line item under operating activities. </td></tr> </tbody></table> <table border="0" cellpadding="0" cellspacing="0" style="width: 100%; text-indent: 0px;"><tbody><tr style="vertical-align: top;"><td style="width: 18pt;"> </td><td style="width: 18pt;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;">●</p> </td><td> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;">Accrued purchases of property and equipment, which were previously reported within the "other" line item under other accrued liabilities in Note <em style="font: inherit;">5,</em> are now reported separately under other accrued liabilities.</p></td></tr> </tbody></table>
CY2019Q4	mpwr	Dividends And Dividend Equivalents Accrued DividendsAndDividendEquivalentsAccrued	21955000	USD
CY2018Q4	mpwr	Dividends And Dividend Equivalents Accrued DividendsAndDividendEquivalentsAccrued	16319000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"><i><b>Use of Estimates</b></i></p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"> </p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;">The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and reported amounts of revenue and expenses during the reporting period. Significant estimates and assumptions used in these consolidated financial statements primarily include those related to revenue recognition, inventory valuation, valuation of share-based awards, contingencies and income tax valuation allowances. Actual results could differ from these estimates and assumptions, and any such differences <em style="font: inherit;"> may</em><i> </i>be material to the Company’s consolidated financial statements. </p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"> </p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;">The COVID-<em style="font: inherit;">19</em> outbreak has significantly affected the global economy and is disrupting business operations worldwide for an unknown period of time until the disease is contained. Although these events did <em style="font: inherit;">not</em><i> </i>adversely affect the Company’s overall operating results and financial condition for the year ended <em style="font: inherit;"> December 31, 2020</em><i>, </i>they could have a negative impact on the Company’s business operations in future periods. However, the Company is currently unable to predict the size and duration of such impact.</p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"> </p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;">As of the date of issuance of these consolidated financial statements, the Company is <em style="font: inherit;">not</em><i> </i>aware of any specific event or circumstance related to the pandemic that would require management to update the significant estimates and assumptions used in the preparation of the consolidated financial statements<i>. </i>As new events continue to evolve and additional information becomes available, any changes to these estimates and assumptions will be recognized in the consolidated financial statements as soon as they become known.</p>
CY2020	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"><i><b>Certain Significant Risks and Uncertainties</b></i></p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"> </p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;">Financial instruments which potentially subject the Company to concentrations of credit risk consist primarily of cash equivalents, short-term and long-term investments and accounts receivable. The Company’s cash equivalents include short-term, highly liquid investments purchased with remaining maturities at the date of purchase of <em style="font: inherit;">three</em> months or less. The Company’s short-term investments <em style="font: inherit;"> may </em>consist of corporate debt securities, certificates of deposit, commercial paper and government agency bonds and treasuries, and the long-term investments consist of government-backed student loan auction-rate securities and non-marketable equity investments.</p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"> </p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;">The Company does <em style="font: inherit;">not</em><i> </i>require its customers to provide collateral to support accounts receivable. The Company assesses the collectability by reviewing accounts receivable on a customer-by-customer basis. To manage credit risk, management performs ongoing credit evaluations of the customers’ financial condition, monitors payment performance, and assesses current economic conditions, as well as reasonable and supportable forecasts of future economic conditions, that <em style="font: inherit;"> may</em><i> </i>affect collectability of the outstanding receivables. For certain high risk customers, the Company requires standby letters of credit or advance payment prior to shipments of goods.</p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"> </p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;">The Company participates in the dynamic high technology industry and believes that changes in any of the following areas could have a material adverse effect on its future financial position, results of operations or cash flows: advances and trends in new technologies and industry standards; competitive pressures in the form of new products or price reductions on current products; changes in product mix; changes in the overall demand for products offered by the Company; changes in <em style="font: inherit;">third</em>-party manufacturers; changes in key suppliers; changes in certain strategic relationships or customer relationships; litigation or claims against the Company based on intellectual property, patent, product, regulatory or other factors; fluctuations in foreign currency exchange rates; risk associated with changes in government policies and regulations on trade restrictions and corporate taxes; availability of necessary components or sub-assemblies; availability of foundry capacity; ability to integrate acquired companies; and the Company’s ability to attract and retain employees necessary to support its growth.</p> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin: 0pt; text-align: left;"> </p>
CY2020Q4	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	46146000	USD
CY2019Q4	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	38858000	USD
CY2020Q4	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	48435000	USD
CY2019Q4	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	40090000	USD
CY2020	mpwr	Lapse Period For Consignment LapsePeriodForConsignment	P60D
CY2020Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	66800000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	52700000	USD
CY2020	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	3400000	USD
CY2020Q4	us-gaap	Cash Cash	300609000	USD
CY2019Q4	us-gaap	Cash Cash	144860000	USD
CY2020Q4	us-gaap	Money Market Funds At Carrying Value MoneyMarketFundsAtCarryingValue	34335000	USD
CY2019Q4	us-gaap	Money Market Funds At Carrying Value MoneyMarketFundsAtCarryingValue	28100000	USD
CY2020Q4	us-gaap	Commercial Paper At Carrying Value CommercialPaperAtCarryingValue	2999000	USD
CY2019Q4	us-gaap	Commercial Paper At Carrying Value CommercialPaperAtCarryingValue	1994000	USD
CY2020Q4	us-gaap	Us Government Securities At Carrying Value USGovernmentSecuritiesAtCarryingValue	7499000	USD
CY2019Q4	us-gaap	Us Government Securities At Carrying Value USGovernmentSecuritiesAtCarryingValue	19493000	USD
CY2020Q4	mpwr	Cash Cash Equivalents And Investments CashCashEquivalentsAndInvestments	597974000	USD
CY2019Q4	mpwr	Cash Cash Equivalents And Investments CashCashEquivalentsAndInvestments	458535000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	334944000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	172960000	USD
CY2020Q4	us-gaap	Short Term Investments ShortTermInvestments	260169000	USD
CY2019Q4	us-gaap	Short Term Investments ShortTermInvestments	282437000	USD
CY2020Q4	us-gaap	Long Term Investments LongTermInvestments	2861000	USD
CY2019Q4	us-gaap	Long Term Investments LongTermInvestments	3138000	USD
CY2020Q4	mpwr	Cash Cash Equivalents And Investments CashCashEquivalentsAndInvestments	597974000	USD
CY2019Q4	mpwr	Cash Cash Equivalents And Investments CashCashEquivalentsAndInvestments	458535000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	97773000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	98036000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	160316000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	162133000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	3020000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	2861000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	261109000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	263030000	USD
CY2020	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	1100000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	295444000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	2179000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	258000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	297365000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	313546000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	390000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	261000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	313675000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	65142000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	99000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	2861000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	159000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	68003000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	258000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	83119000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	64000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	14274000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	197000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	97393000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	261000	USD
CY2020	mpwr	Redemption Auction Rate Securities To Date RedemptionAuctionRateSecuritiesToDate	40300000	USD
CY2020	mpwr	Percentage Of Auction Rate Securities Redeemedat Par Value PercentageOfAuctionRateSecuritiesRedeemedatParValue	0.93	pure
CY2020Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	3400000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	334944000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	172960000	USD
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	127000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	116000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	335071000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	173076000	USD
CY2020Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	324289000	USD
CY2019Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	335650000	USD
CY2020Q4	mpwr	Product Return Assets Current ProductReturnAssetsCurrent	1684000	USD
CY2020Q4	us-gaap	Inventory Raw Materials Net Of Reserves InventoryRawMaterialsNetOfReserves	25503000	USD
CY2019Q4	us-gaap	Inventory Raw Materials Net Of Reserves InventoryRawMaterialsNetOfReserves	22872000	USD
CY2020Q4	us-gaap	Inventory Work In Process Net Of Reserves InventoryWorkInProcessNetOfReserves	77100000	USD
CY2019Q4	us-gaap	Inventory Work In Process Net Of Reserves InventoryWorkInProcessNetOfReserves	42681000	USD
CY2020Q4	us-gaap	Inventory Finished Goods Net Of Reserves InventoryFinishedGoodsNetOfReserves	54459000	USD
CY2019Q4	us-gaap	Inventory Finished Goods Net Of Reserves InventoryFinishedGoodsNetOfReserves	61947000	USD
CY2020Q4	us-gaap	Inventory Net InventoryNet	157062000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	127500000	USD
CY2020Q4	mpwr	Tax Withholding Share Based Payment Arrangement Proceeds Receivable TaxWithholdingShareBasedPaymentArrangementProceedsReceivable	12504000	USD
CY2019Q4	mpwr	Tax Withholding Share Based Payment Arrangement Proceeds Receivable TaxWithholdingShareBasedPaymentArrangementProceedsReceivable	6106000	USD
CY2020Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	5032000	USD
CY2019Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	7991000	USD
CY2020Q4	us-gaap	Interest Receivable Current InterestReceivableCurrent	1914000	USD
CY2019Q4	us-gaap	Interest Receivable Current InterestReceivableCurrent	2490000	USD
CY2019Q4	mpwr	Product Return Assets Current ProductReturnAssetsCurrent	1585000	USD
CY2020Q4	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	1846000	USD
CY2019Q4	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	1433000	USD
CY2020Q4	us-gaap	Other Assets Current OtherAssetsCurrent	22980000	USD
CY2019Q4	us-gaap	Other Assets Current OtherAssetsCurrent	19605000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	424677000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	347246000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	143149000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	118931000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	281528000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	228315000	USD
CY2020	us-gaap	Depreciation Depreciation	18900000	USD
CY2019	us-gaap	Depreciation Depreciation	14500000	USD
CY2018	us-gaap	Depreciation Depreciation	11400000	USD
CY2020Q4	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	46146000	USD
CY2019Q4	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	38858000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	3719000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	2863000	USD
CY2020Q4	us-gaap	Prepaid Expense Other Noncurrent PrepaidExpenseOtherNoncurrent	2340000	USD
CY2019Q4	us-gaap	Prepaid Expense Other Noncurrent PrepaidExpenseOtherNoncurrent	2687000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities Noncurrent AvailableForSaleSecuritiesDebtSecuritiesNoncurrent	2861000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities Noncurrent AvailableForSaleSecuritiesDebtSecuritiesNoncurrent	3138000	USD
CY2020Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	3400000	USD
CY2019Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	0	USD
CY2020Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	1372000	USD
CY2019Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	1544000	USD
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	59838000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	49090000	USD
CY2020Q4	mpwr	Dividends And Dividend Equivalents DividendsAndDividendEquivalents	26435000	USD
CY2019Q4	mpwr	Dividends And Dividend Equivalents DividendsAndDividendEquivalents	21747000	USD
CY2020Q4	mpwr	Stock Rotation Reserve And Accrued Sales Returns StockRotationReserveAndAccruedSalesReturns	6005000	USD
CY2019Q4	mpwr	Stock Rotation Reserve And Accrued Sales Returns StockRotationReserveAndAccruedSalesReturns	5530000	USD
CY2020Q4	mpwr	Accrued Purchases Of Property And Equipment Current AccruedPurchasesOfPropertyAndEquipmentCurrent	5841000	USD
CY2019Q4	mpwr	Accrued Purchases Of Property And Equipment Current AccruedPurchasesOfPropertyAndEquipmentCurrent	4678000	USD
CY2020Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	3755000	USD
CY2019Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	2435000	USD
CY2020Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	7238000	USD
CY2019Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	3412000	USD
CY2020Q4	us-gaap	Accrued Sales Commission Current AccruedSalesCommissionCurrent	1107000	USD
CY2019Q4	us-gaap	Accrued Sales Commission Current AccruedSalesCommissionCurrent	1425000	USD
CY2020Q4	us-gaap	Product Warranty Accrual Classified Current ProductWarrantyAccrualClassifiedCurrent	6895000	USD
CY2019Q4	us-gaap	Product Warranty Accrual Classified Current ProductWarrantyAccrualClassifiedCurrent	1139000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	4278000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	3170000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	62960000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	44790000	USD
CY2019Q1	us-gaap	Payments To Acquire Real Estate PaymentsToAcquireRealEstate	52900000	USD
CY2019Q1	mpwr	Real Estate Capitalized Transaction Costs RealEstateCapitalizedTransactionCosts	400000	USD
CY2020Q4	us-gaap	Deferred Compensation Liability Classified Noncurrent DeferredCompensationLiabilityClassifiedNoncurrent	48280000	USD
CY2019Q4	us-gaap	Deferred Compensation Liability Classified Noncurrent DeferredCompensationLiabilityClassifiedNoncurrent	39665000	USD
CY2020Q4	mpwr	Dividend Equivalents Noncurrent DividendEquivalentsNoncurrent	7871000	USD
CY2019Q4	mpwr	Dividend Equivalents Noncurrent DividendEquivalentsNoncurrent	6265000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	29000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	30000	USD
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	57873000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	47063000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	1488000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	1509000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	300000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	465000	USD
CY2020	us-gaap	Lease Cost LeaseCost	1788000	USD
CY2019	us-gaap	Lease Cost LeaseCost	1974000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	1526000	USD
	us-gaap	Operating Lease Payments OperatingLeasePayments	1364000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	2181000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	3667000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P2Y8M12D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P2Y1M6D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.027	pure
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.037	pure
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	1491000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	993000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	405000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	199000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	139000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	3227000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	128000	USD
CY2020Q4	mpwr	Lessee Operating Lease Lease Not Yet Commenced Future Lease Obligations LesseeOperatingLeaseLeaseNotYetCommencedFutureLeaseObligations	4600000	USD
CY2020	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	1900000	USD
CY2019	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	1800000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Next Twelve Months LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths	2153000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Two Years LessorOperatingLeasePaymentsToBeReceivedTwoYears	2073000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Three Years LessorOperatingLeasePaymentsToBeReceivedThreeYears	1400000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Four Years LessorOperatingLeasePaymentsToBeReceivedFourYears	553000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Five Years LessorOperatingLeasePaymentsToBeReceivedFiveYears	59000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received LessorOperatingLeasePaymentsToBeReceived	6238000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	85551000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	78699000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	60607000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	1855000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	2754000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4383000	USD
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	4144000
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	39.91
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	1363000
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	80.62
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	853000
CY2019	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	7305000	USD
CY2018	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	6321000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue	44.13
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	21000
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	76.92
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	4633000
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	50.94
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	564000
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	103.68
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	1083000
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue	47.34
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-2979000	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-729000	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-1353000	USD
CY2020	mpwr	Gain Loss On Deferred Compensation Plan Investments GainLossOnDeferredCompensationPlanInvestments	4592000	USD
CY2019	mpwr	Gain Loss On Deferred Compensation Plan Investments GainLossOnDeferredCompensationPlanInvestments	3806000	USD
CY2018	mpwr	Gain Loss On Deferred Compensation Plan Investments GainLossOnDeferredCompensationPlanInvestments	-1022000	USD
CY2020	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-1364000	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-310000	USD
CY2018	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	953000	USD
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	884000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	486000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	95000	USD
CY2020	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	10460000	USD
CY2019	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	10558000	USD
CY2018	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	4994000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	61000
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	57.01
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	4053000
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	59.16
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	703000
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	175.12
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	1623000
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue	54.70
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	28000
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	96.35
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	3105000
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	87.42
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.00
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.60
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.20
CY2020	us-gaap	Dividends Common Stock DividendsCommonStock	89832000	USD
CY2019	us-gaap	Dividends Common Stock DividendsCommonStock	69196000	USD
CY2018	us-gaap	Dividends Common Stock DividendsCommonStock	50803000	USD
CY2020Q4	us-gaap	Dividends Payable Current DividendsPayableCurrent	22600000	USD
CY2019Q4	us-gaap	Dividends Payable Current DividendsPayableCurrent	17400000	USD
CY2020Q4	mpwr	Accrued Dividend Equivalents AccruedDividendEquivalents	11700000	USD
CY2019Q4	mpwr	Accrued Dividend Equivalents AccruedDividendEquivalents	10600000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	-4134000	USD
CY2020	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	9327000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	164375000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	108839000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105268000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	44840000
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	43165000
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	42247000
CY2020	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	2174000
CY2019	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	2598000
CY2018	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	2355000
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	47014000
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	45763000
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	44602000
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.67
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.52
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.49
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.50
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.38
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.36
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	39286000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	-13151000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	130056000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	117254000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	131633000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	169342000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	113120000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	118482000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	2842000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	1682000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	11023000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-1000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	8000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	4000	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	3814000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	3105000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	2992000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-1221000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-213000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-797000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-467000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-301000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-8000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4967000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4281000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13214000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210	pure
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210	pure
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210	pure
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.152	pure
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.207	pure
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.220	pure
CY2020	mpwr	Effective Income Tax Rate Reconciliation Repatriation Transition Tax EffectiveIncomeTaxRateReconciliationRepatriationTransitionTax	0	pure
CY2019	mpwr	Effective Income Tax Rate Reconciliation Repatriation Transition Tax EffectiveIncomeTaxRateReconciliationRepatriationTransitionTax	0	pure
CY2018	mpwr	Effective Income Tax Rate Reconciliation Repatriation Transition Tax EffectiveIncomeTaxRateReconciliationRepatriationTransitionTax	0.006	pure
CY2020	mpwr	Effective Income Tax Rate Reconciliation Global Intangible Low Taxed Income EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncome	0.111	pure
CY2019	mpwr	Effective Income Tax Rate Reconciliation Global Intangible Low Taxed Income EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncome	0.110	pure
CY2018	mpwr	Effective Income Tax Rate Reconciliation Global Intangible Low Taxed Income EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncome	0.144	pure
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.016	pure
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.021	pure
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	pure
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.112	pure
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.015	pure
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.011	pure
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	24300000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	25400000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	17300000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.038	pure
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.062	pure
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.019	pure
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	-0.016	pure
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	-0.007	pure
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0	pure
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.010	pure
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.012	pure
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.002	pure
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.029	pure
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.038	pure
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.112	pure
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	23501000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	18080000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	2392000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	6237000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	7895000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	7110000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	1150000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	615000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	4617000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	2323000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	39555000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	34365000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	18190000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	15411000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	21365000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	18954000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1600000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1259000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	77000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	77000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	1132000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	425000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	2809000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	1761000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	18556000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	17193000	USD
CY2020Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	27700000	USD
CY2019Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	32900000	USD
CY2020	mpwr	Dividend Received Deduction On Undistributed Earnings DividendReceivedDeductionOnUndistributedEarnings	1	pure
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	33500000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	16272000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1474000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	2957000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	212000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	20491000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1589000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	4663000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	560000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	776000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	25407000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	9782000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	907000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	560000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	223000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	33499000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	2400000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	1600000	USD
CY2019Q4	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	1139000	USD
CY2018Q4	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	4564000	USD
CY2017Q4	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	2416000	USD
CY2020	us-gaap	Standard Product Warranty Accrual Warranties Issued StandardProductWarrantyAccrualWarrantiesIssued	7584000	USD
CY2019	us-gaap	Standard Product Warranty Accrual Warranties Issued StandardProductWarrantyAccrualWarrantiesIssued	891000	USD
CY2018	us-gaap	Standard Product Warranty Accrual Warranties Issued StandardProductWarrantyAccrualWarrantiesIssued	6586000	USD
CY2020	us-gaap	Product Warranty Accrual Payments ProductWarrantyAccrualPayments	843000	USD
CY2019	us-gaap	Product Warranty Accrual Payments ProductWarrantyAccrualPayments	2768000	USD
CY2018	us-gaap	Product Warranty Accrual Payments ProductWarrantyAccrualPayments	1402000	USD
CY2020	us-gaap	Product Warranty Accrual Preexisting Increase Decrease ProductWarrantyAccrualPreexistingIncreaseDecrease	985000	USD
CY2019	us-gaap	Product Warranty Accrual Preexisting Increase Decrease ProductWarrantyAccrualPreexistingIncreaseDecrease	1548000	USD
CY2018	us-gaap	Product Warranty Accrual Preexisting Increase Decrease ProductWarrantyAccrualPreexistingIncreaseDecrease	3036000	USD
CY2020Q4	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	6895000	USD
CY2019Q4	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	1139000	USD
CY2018Q4	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	4564000	USD
CY2020Q4	us-gaap	Purchase Obligation PurchaseObligation	211500000	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	1	pure
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	844452000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	627921000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	582382000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	844452000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	627921000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	582382000	USD
CY2020Q4	us-gaap	Noncurrent Assets NoncurrentAssets	281528000	USD
CY2019Q4	us-gaap	Noncurrent Assets NoncurrentAssets	228315000	USD
CY2018Q4	us-gaap	Noncurrent Assets NoncurrentAssets	150001000	USD

Files In Submission

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0001437749-21-004587.txt	Edgar Link	pending
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$MPWR
Monolithic Power Systems Inc Stock $mpwr

2019 Q4 Form 10-K Financial Statement

#000143774921004587 Filed on March 01, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

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$MPWR Monolithic Power Systems Inc Stock $mpwr

2019 Q4 Form 10-K Financial Statement

#000143774921004587 Filed on March 01, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MPWR
Monolithic Power Systems Inc Stock $mpwr