$MMC
MARSH & MCLENNAN COMPANIES, INC. Stock $mmc

$mmc Overview Financials Valuation SEC Filings Company Website

2023 Q1 Form 10-K Financial Statement

#000006270923000014 Filed on February 13, 2023

Income Statement

Concept	2023 Q1	2022 Q4	2022
Revenue	$5.924B	$5.022B	$20.72B
YoY Change	6.76%	-2.24%	4.54%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin	$3.207B	$3.038B	$12.07B
YoY Change	3.45%	4.58%	5.65%
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$84.00M	$460.0M	$719.0M
YoY Change	-5.62%	158.43%	-3.75%
% of Gross Profit
Operating Expenses	$4.198B	$4.342B	$16.44B
YoY Change	2.29%	5.41%	6.01%
Operating Profit	$1.726B		$4.280B
YoY Change	19.45%		-0.74%
Interest Expense	$136.0M	-$124.0M	-$433.0M
YoY Change	23.64%	36.26%	-197.52%
% of Operating Profit	7.88%		-10.12%
Other Income/Expense, Net	$58.00M	$57.00M	$235.0M
YoY Change	-6.45%	-13.64%	-15.16%
Pretax Income	$1.664B	$613.0M	$4.082B
YoY Change	16.85%	-36.21%	-2.99%
Income Tax	$412.0M	$142.0M	$995.0M
% Of Pretax Income	24.76%	23.16%	24.38%
Net Earnings	$1.235B	$466.0M	$3.050B
YoY Change	15.31%	-41.97%	-2.96%
Net Earnings / Revenue	20.85%	9.28%	14.72%
Basic Earnings Per Share	$2.50		$6.11
Diluted Earnings Per Share	$2.47	$930.1K	$6.040M
COMMON SHARES
Basic Shares Outstanding	494.6M shares	496.0M shares	499.0M shares
Diluted Shares Outstanding	500.0M shares		505.0M shares

Balance Sheet

Concept	2023 Q1	2022 Q4	2022
SHORT-TERM ASSETS
Cash & Short-Term Investments	$1.006B	$1.442B	$1.442B
YoY Change	30.31%	-17.69%	-17.69%
Cash & Equivalents	$1.006B	$1.442B	$1.442B
Short-Term Investments
Other Short-Term Assets	$1.407B	$1.005B	$1.005B
YoY Change	33.62%	8.53%	58.02%
Inventory
Prepaid Expenses
Receivables	$7.066B	$5.852B	$5.852B
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$9.113B	$8.299B	$8.299B
YoY Change	17.01%	0.42%	0.42%
LONG-TERM ASSETS
Property, Plant & Equipment	$867.0M	$2.433B	$2.433B
YoY Change	0.23%	187.25%	-10.39%
Goodwill	$16.30B	$16.25B
YoY Change	0.28%	-0.4%
Intangibles		$2.537B
YoY Change		-9.72%
Long-Term Investments	$214.0M	$215.0M	$215.0M
YoY Change	-4.46%	3.86%	3.86%
Other Assets	$1.471B	$3.934B	$3.934B
YoY Change	0.75%	169.27%	-3.46%
Total Long-Term Assets	$25.25B	$25.16B	$25.16B
YoY Change	-2.53%	-3.71%	-3.71%
TOTAL ASSETS
Total Short-Term Assets	$9.113B	$8.299B	$8.299B
Total Long-Term Assets	$25.25B	$25.16B	$25.16B
Total Assets	$34.36B	$33.45B	$33.45B
YoY Change	1.99%	-2.72%	-2.72%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$3.406B	$3.278B	$3.278B
YoY Change	10.44%	3.57%	3.57%
Accrued Expenses	$1.749B	$3.405B	$3.405B
YoY Change	1.04%	4.0%	4.0%
Deferred Revenue
YoY Change
Short-Term Debt	$844.0M	$268.0M	$0.00
YoY Change	2.3%	1476.47%
Long-Term Debt Due	$1.267B	$268.0M	$268.0M
YoY Change	246.17%	1476.47%	1476.47%
Total Short-Term Liabilities	$7.914B	$7.172B	$7.172B
YoY Change	20.15%	7.78%	7.78%
LONG-TERM LIABILITIES
Long-Term Debt	$10.84B	$11.23B	$11.23B
YoY Change	2.74%	2.69%	2.69%
Other Long-Term Liabilities	$1.433B	$4.306B	$4.306B
YoY Change	-15.46%	151.52%	-22.82%
Total Long-Term Liabilities	$12.27B	$15.53B	$15.53B
YoY Change	0.22%	22.84%	-5.93%
TOTAL LIABILITIES
Total Short-Term Liabilities	$7.914B	$7.172B	$7.172B
Total Long-Term Liabilities	$12.27B	$15.53B	$15.53B
Total Liabilities	$20.19B	$22.71B	$22.71B
YoY Change	7.19%	17.65%	-2.88%
SHAREHOLDERS EQUITY
Retained Earnings	$20.95B	$20.30B
YoY Change	10.75%	10.4%
Common Stock	$1.625B	$1.740B
YoY Change	2.39%	4.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$10.95B	$10.75B	$10.75B
YoY Change
Total Liabilities & Shareholders Equity	$34.36B	$33.45B	$33.45B
YoY Change	1.99%	-2.72%	-2.72%

Cashflow Statement

Concept	2023 Q1	2022 Q4	2022
OPERATING ACTIVITIES
Net Income	$1.235B	$466.0M	$3.050B
YoY Change	15.31%	-41.97%	-2.96%
Depreciation, Depletion And Amortization	$84.00M	$460.0M	$719.0M
YoY Change	-5.62%	158.43%	-3.75%
Cash From Operating Activities	-$819.0M	$1.502B	$3.465B
YoY Change	16.67%	4.16%	-1.45%
INVESTING ACTIVITIES
Capital Expenditures	$84.00M	-$103.0M	-$470.0M
YoY Change	-31.15%	-25.36%	-215.76%
Acquisitions			$572.0M
YoY Change			-33.41%
Other Investing Activities	-$3.000M	-$384.0M	-$380.0M
YoY Change	-400.0%	-12.13%	9400.0%
Cash From Investing Activities	-$368.0M	-$487.0M	-$850.0M
YoY Change	131.45%	-15.3%	-26.98%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			-$2.022B
YoY Change			-274.46%
Debt Paid & Issued, Net	$4.000M		$365.0M
YoY Change	0.0%		-64.07%
Cash From Financing Activities	$773.0M	-1.074B	-1.046B
YoY Change	-9.59%	-243.39%	-19.35%
NET CHANGE
Cash From Operating Activities	-$819.0M	1.502B	3.465B
Cash From Investing Activities	-$368.0M	-487.0M	-850.0M
Cash From Financing Activities	$773.0M	-1.074B	-1.046B
Net Change In Cash	-$262.0M	-59.00M	1.569B
YoY Change	84.51%	-103.65%	124.14%
FREE CASH FLOW
Cash From Operating Activities	-$819.0M	$1.502B	$3.465B
Capital Expenditures	$84.00M	-$103.0M	-$470.0M
Free Cash Flow	-$903.0M	$1.605B	$3.935B
YoY Change	9.59%	1.58%	26.53%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2022	dei	Entity Central Index Key EntityCentralIndexKey	0000062709
CY2022	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2022
CY2022	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
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CY2022Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2022Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2022Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1
CY2022	dei	Document Type DocumentType	10-K
CY2022	dei	Document Annual Report DocumentAnnualReport	true
CY2022	dei	Document Period End Date DocumentPeriodEndDate	2022-12-31
CY2022	dei	Document Period End Date DocumentPeriodEndDate	2022-12-31
CY2022	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2022	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2022	dei	Document Transition Report DocumentTransitionReport	false
CY2022	dei	Entity File Number EntityFileNumber	1-5998
CY2022	dei	Entity Registrant Name EntityRegistrantName	Marsh & McLennan Companies, Inc.
CY2022	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2022	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	36-2668272
CY2022	dei	Entity Address Address Line1 EntityAddressAddressLine1	1166 Avenue of the Americas
CY2022	dei	Entity Address City Or Town EntityAddressCityOrTown	New York
CY2022	dei	Entity Address State Or Province EntityAddressStateOrProvince	NY
CY2022	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	10036
CY2022	dei	City Area Code CityAreaCode	212
CY2022	dei	Local Phone Number LocalPhoneNumber	345-5000
CY2022	dei	Security12b Title Security12bTitle	Common Stock, par value $1.00 per share
CY2022	dei	Trading Symbol TradingSymbol	MMC
CY2022	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2022	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2022	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2022	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2022	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2022	dei	Entity Small Business EntitySmallBusiness	false
CY2022	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2022	dei	Entity Shell Company EntityShellCompany	false
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CY2022	dei	Auditor Name AuditorName	Deloitte & Touche LLP
CY2022	dei	Auditor Location AuditorLocation	New York, New York
CY2022	dei	Auditor Firm AuditorFirmId	34
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CY2022Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	221000000	usd
CY2021Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	198000000	usd
CY2022Q4	us-gaap	Liabilities Current LiabilitiesCurrent	7172000000	usd
CY2021Q4	us-gaap	Liabilities Current LiabilitiesCurrent	6654000000	usd
CY2022Q4	mmc	Fiduciary Liabilities Gross Noncurrent FiduciaryLiabilitiesGrossNoncurrent	10660000000	usd
CY2021Q4	mmc	Fiduciary Liabilities Gross Noncurrent FiduciaryLiabilitiesGrossNoncurrent	9622000000	usd
CY2022Q4	mmc	Cashand Investments Heldin Fiduciary Capacity Noncurrent CashandInvestmentsHeldinFiduciaryCapacityNoncurrent	10660000000	usd
CY2021Q4	mmc	Cashand Investments Heldin Fiduciary Capacity Noncurrent CashandInvestmentsHeldinFiduciaryCapacityNoncurrent	9622000000	usd
CY2022Q4	mmc	Fiduciary Liabilities Net Noncurrent FiduciaryLiabilitiesNetNoncurrent	0	usd
CY2021Q4	mmc	Fiduciary Liabilities Net Noncurrent FiduciaryLiabilitiesNetNoncurrent	0	usd
CY2022Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	11227000000	usd
CY2021Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	10933000000	usd
CY2022Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	921000000	usd
CY2021Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	1632000000	usd
CY2022Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	1667000000	usd
CY2021Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	1880000000	usd
CY2022Q4	mmc	Liability For Errors And Omissions LiabilityForErrorsAndOmissions	355000000	usd
CY2021Q4	mmc	Liability For Errors And Omissions LiabilityForErrorsAndOmissions	355000000	usd
CY2022Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	1363000000	usd
CY2021Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	1712000000	usd
CY2022Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies	0	usd
CY2021Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies	0	usd
CY2022Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	1
CY2021Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	1
CY2021Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	6000000	shares
CY2022Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	6000000	shares
CY2022Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2021Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2022Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	usd
CY2021Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	usd
CY2021Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1
CY2022Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1
CY2021Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	1600000000	shares
CY2022Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	1600000000	shares
CY2021Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	560641640	shares
CY2022Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	560641640	shares
CY2022Q4	us-gaap	Common Stock Value CommonStockValue	561000000	usd
CY2021Q4	us-gaap	Common Stock Value CommonStockValue	561000000	usd
CY2022Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	1179000000	usd
CY2021Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	1112000000	usd
CY2022Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	20301000000	usd
CY2021Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	18389000000	usd
CY2022Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-5314000000	usd
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-4575000000	usd
CY2022Q4	us-gaap	Minority Interest MinorityInterest	229000000	usd
CY2021Q4	us-gaap	Minority Interest MinorityInterest	213000000	usd
CY2022Q4	mmc	Stockholders Equity Subtotal Before Treasury Stock StockholdersEquitySubtotalBeforeTreasuryStock	16956000000	usd
CY2021Q4	mmc	Stockholders Equity Subtotal Before Treasury Stock StockholdersEquitySubtotalBeforeTreasuryStock	15700000000	usd
CY2022Q4	us-gaap	Treasury Stock Common Shares TreasuryStockCommonShares	65855914	shares
CY2021Q4	us-gaap	Treasury Stock Common Shares TreasuryStockCommonShares	57105619	shares
CY2022Q4	us-gaap	Treasury Stock Common Value TreasuryStockCommonValue	6207000000	usd
CY2021Q4	us-gaap	Treasury Stock Common Value TreasuryStockCommonValue	4478000000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	10749000000	usd
CY2021Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	11222000000	usd
CY2022Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	33454000000	usd
CY2021Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	34388000000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	3087000000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	3174000000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	2046000000	usd
CY2022	us-gaap	Depreciation Depreciation	381000000	usd
CY2021	us-gaap	Depreciation Depreciation	382000000	usd
CY2020	us-gaap	Depreciation Depreciation	390000000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	338000000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	365000000	usd
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	351000000	usd
CY2022	mmc	Leases Right Of Use Asset Amortization LeasesRightOfUseAssetAmortization	404000000	usd
CY2021	mmc	Leases Right Of Use Asset Amortization LeasesRightOfUseAssetAmortization	327000000	usd
CY2020	mmc	Leases Right Of Use Asset Amortization LeasesRightOfUseAssetAmortization	355000000	usd
CY2022	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	11000000	usd
CY2021	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	27000000	usd
CY2020	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	-22000000	usd
CY2022	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	-39000000	usd
CY2021	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	0	usd
CY2020	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	0	usd
CY2022	mmc	Consolidation Gain Loss Amount ConsolidationGainLossAmount	2000000	usd
CY2021	mmc	Consolidation Gain Loss Amount ConsolidationGainLossAmount	267000000	usd
CY2020	mmc	Consolidation Gain Loss Amount ConsolidationGainLossAmount	0	usd
CY2022	us-gaap	Gain Loss On Investments GainLossOnInvestments	21000000	usd
CY2021	us-gaap	Gain Loss On Investments GainLossOnInvestments	61000000	usd
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	-22000000	usd
CY2022	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	127000000	usd
CY2021	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	33000000	usd
CY2020	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	-24000000	usd
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	367000000	usd
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	348000000	usd
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	290000000	usd
CY2022	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	492000000	usd
CY2021	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	570000000	usd
CY2020	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-412000000	usd
CY2022	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	122000000	usd
CY2021	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	354000000	usd
CY2020	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-255000000	usd
CY2022	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	171000000	usd
CY2021	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	574000000	usd
CY2020	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	171000000	usd
CY2022	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-54000000	usd
CY2021	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-33000000	usd
CY2020	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	63000000	usd
CY2022	mmc	Pensionand Other Postretirement Benefit Contributions In Excessof Current Year Expense PensionandOtherPostretirementBenefitContributionsInExcessofCurrentYearExpense	385000000	usd
CY2021	mmc	Pensionand Other Postretirement Benefit Contributions In Excessof Current Year Expense PensionandOtherPostretirementBenefitContributionsInExcessofCurrentYearExpense	372000000	usd
CY2020	mmc	Pensionand Other Postretirement Benefit Contributions In Excessof Current Year Expense PensionandOtherPostretirementBenefitContributionsInExcessofCurrentYearExpense	356000000	usd
CY2022	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	193000000	usd
CY2021	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	358000000	usd
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-268000000	usd
CY2022	mmc	Increase Decreasein Operating Lease Liabilities IncreaseDecreaseinOperatingLeaseLiabilities	-323000000	usd
CY2021	mmc	Increase Decreasein Operating Lease Liabilities IncreaseDecreaseinOperatingLeaseLiabilities	-349000000	usd
CY2020	mmc	Increase Decreasein Operating Lease Liabilities IncreaseDecreaseinOperatingLeaseLiabilities	-351000000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	3465000000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	3516000000	usd
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	3382000000	usd
CY2022	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1950000000	usd
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1159000000	usd
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	usd
CY2022	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	0	usd
CY2021	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	0	usd
CY2020	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	1000000000	usd
CY2022	us-gaap	Proceeds From Issuance Of Debt ProceedsFromIssuanceOfDebt	984000000	usd
CY2021	us-gaap	Proceeds From Issuance Of Debt ProceedsFromIssuanceOfDebt	743000000	usd
CY2020	us-gaap	Proceeds From Issuance Of Debt ProceedsFromIssuanceOfDebt	737000000	usd
CY2022	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	365000000	usd
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	1016000000	usd
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	2515000000	usd
CY2022	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	7000000	usd
CY2021	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	0	usd
CY2020	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	3000000	usd
CY2022	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	198000000	usd
CY2021	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	101000000	usd
CY2020	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	132000000	usd
CY2022	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	126000000	usd
CY2021	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	161000000	usd
CY2020	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	132000000	usd
CY2022	mmc	Paymentsfor Acquisitions Deferredand Contingent Consideration PaymentsforAcquisitionsDeferredandContingentConsideration	158000000	usd
CY2021	mmc	Paymentsfor Acquisitions Deferredand Contingent Consideration PaymentsforAcquisitionsDeferredandContingentConsideration	117000000	usd
CY2020	mmc	Paymentsfor Acquisitions Deferredand Contingent Consideration PaymentsforAcquisitionsDeferredandContingentConsideration	122000000	usd
CY2022	mmc	Receipts Of Contingent Consideration For Dispositions ReceiptsOfContingentConsiderationForDispositions	3000000	usd
CY2021	mmc	Receipts Of Contingent Consideration For Dispositions ReceiptsOfContingentConsiderationForDispositions	71000000	usd
CY2020	mmc	Receipts Of Contingent Consideration For Dispositions ReceiptsOfContingentConsiderationForDispositions	0	usd
CY2022	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	27000000	usd
CY2021	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	36000000	usd
CY2020	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	34000000	usd
CY2022	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1138000000	usd
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1026000000	usd
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	943000000	usd
CY2022	mmc	Increase Decrease In Fiduciary Liabilities IncreaseDecreaseInFiduciaryLiabilities	1684000000	usd
CY2021	mmc	Increase Decrease In Fiduciary Liabilities IncreaseDecreaseInFiduciaryLiabilities	1183000000	usd
CY2020	mmc	Increase Decrease In Fiduciary Liabilities IncreaseDecreaseInFiduciaryLiabilities	955000000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1046000000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1297000000	usd
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-925000000	usd
CY2022	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	470000000	usd
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	406000000	usd
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	348000000	usd
CY2022	us-gaap	Payments To Acquire Longterm Investments PaymentsToAcquireLongtermInvestments	22000000	usd
CY2021	us-gaap	Payments To Acquire Longterm Investments PaymentsToAcquireLongtermInvestments	28000000	usd
CY2020	us-gaap	Payments To Acquire Longterm Investments PaymentsToAcquireLongtermInvestments	23000000	usd
CY2022	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	86000000	usd
CY2021	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	41000000	usd
CY2020	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	130000000	usd
CY2022	us-gaap	Proceeds From Divestiture Of Businesses And Interests In Affiliates ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates	119000000	usd
CY2021	us-gaap	Proceeds From Divestiture Of Businesses And Interests In Affiliates ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates	84000000	usd
CY2020	us-gaap	Proceeds From Divestiture Of Businesses And Interests In Affiliates ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates	98000000	usd
CY2022	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	572000000	usd
CY2021	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	859000000	usd
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	647000000	usd
CY2022	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-9000000	usd
CY2021	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-4000000	usd
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	3000000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-850000000	usd
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1164000000	usd
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-793000000	usd
CY2022	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-841000000	usd
CY2021	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-355000000	usd
CY2020	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	511000000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	728000000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	700000000	usd
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	2175000000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	11374000000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	10674000000	usd
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	8499000000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	12102000000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	11374000000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	10674000000	usd
CY2022Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1442000000	usd
CY2021Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1752000000	usd
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	2089000000	usd
CY2022Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	10660000000	usd
CY2021Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	9622000000	usd
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	8585000000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	12102000000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	11374000000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	10674000000	usd
CY2022	mmc	Dividend Equivalents Per Share Cash Declared DividendEquivalentsPerShareCashDeclared	2.25
CY2021	mmc	Dividend Equivalents Per Share Cash Declared DividendEquivalentsPerShareCashDeclared	2.00
CY2020	mmc	Dividend Equivalents Per Share Cash Declared DividendEquivalentsPerShareCashDeclared	1.84
CY2022	mmc	Common Stock Dividends Per Share Cash Declared CommonStockDividendsPerShareCashDeclared	2.25
CY2021	mmc	Common Stock Dividends Per Share Cash Declared CommonStockDividendsPerShareCashDeclared	2.00
CY2020	mmc	Common Stock Dividends Per Share Cash Declared CommonStockDividendsPerShareCashDeclared	1.84
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	10749000000	usd
CY2021Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	11222000000	usd
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	9260000000	usd
CY2022Q1	mmc	Deconsolidation Gain Loss And Other Charges Amount DeconsolidationGainLossAndOtherChargesAmount	-52000000	usd
CY2022Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	348000000	usd
CY2021Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	303000000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	2402000000	usd
CY2021Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	2436000000	usd
CY2022Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1531000000	usd
CY2021Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1589000000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	871000000	usd
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	847000000	usd
CY2022	us-gaap	Gain Loss On Investments GainLossOnInvestments	21000000	usd
CY2021	us-gaap	Gain Loss On Investments GainLossOnInvestments	61000000	usd
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	-22000000	usd
CY2022Q4	us-gaap	Capitalized Computer Software Net CapitalizedComputerSoftwareNet	492000000	usd
CY2021Q4	us-gaap	Capitalized Computer Software Net CapitalizedComputerSoftwareNet	475000000	usd
CY2022Q4	us-gaap	Capitalized Computer Software Accumulated Amortization CapitalizedComputerSoftwareAccumulatedAmortization	1800000000	usd
CY2021Q4	us-gaap	Capitalized Computer Software Accumulated Amortization CapitalizedComputerSoftwareAccumulatedAmortization	1700000000	usd
CY2022Q4	mmc	Liability For Errors And Omissions Current And Noncurrent LiabilityForErrorsAndOmissionsCurrentAndNoncurrent	419000000	usd
CY2021Q4	mmc	Liability For Errors And Omissions Current And Noncurrent LiabilityForErrorsAndOmissionsCurrentAndNoncurrent	434000000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	3087000000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	3174000000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	2046000000	usd
CY2022	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	37000000	usd
CY2021	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	31000000	usd
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	30000000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	3050000000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	3143000000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	2016000000	usd
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	499000000	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	507000000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	506000000	shares
CY2022	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	6000000	shares
CY2021	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	6000000	shares
CY2020	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	6000000	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	505000000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	513000000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	512000000	shares
CY2022	mmc	Average Share Price Common Stock AverageSharePriceCommonStock	160.39
CY2021	mmc	Average Share Price Common Stock AverageSharePriceCommonStock	141.57
CY2020	mmc	Average Share Price Common Stock AverageSharePriceCommonStock	109.12
CY2022Q4	mmc	Uncollected Premiumsand Claims Netof Related Payables UncollectedPremiumsandClaimsNetofRelatedPayables	13000000000	usd
CY2021Q4	mmc	Uncollected Premiumsand Claims Netof Related Payables UncollectedPremiumsandClaimsNetofRelatedPayables	13000000000	usd
CY2022	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Estimates:</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> T</span><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">he preparation of the consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expense during the reporting period. </span></div><div style="margin-top:5pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">On an ongoing basis, the Company evaluates its estimates, judgments and methodologies. The estimates are based on historical experience and on various other assumptions that the Company believes are reasonable. </span></div><div style="margin-top:5pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Such matters include:</span></div><div style="margin-top:5pt;padding-left:36pt;text-indent:-18pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">estimates of revenue;</span></div><div style="margin-top:5pt;padding-left:36pt;text-indent:-18pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">impairment assessments and charges;</span></div><div style="margin-top:5pt;padding-left:36pt;text-indent:-18pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">recoverability of long-lived assets;</span></div><div style="margin-top:5pt;padding-left:36pt;text-indent:-18pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">liabilities for errors and omissions;</span></div><div style="margin-top:5pt;padding-left:36pt;text-indent:-18pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">deferred tax assets, uncertain tax positions and income tax expense;</span></div><div style="margin-top:5pt;padding-left:36pt;text-indent:-18pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">share-based and incentive compensation expense; </span></div><div style="margin-top:5pt;padding-left:36pt;text-indent:-18pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">the allowance for current expected credit losses on receivables;</span></div><div style="margin-top:5pt;padding-left:36pt;text-indent:-18pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">useful lives assigned to long-lived assets, and depreciation and amortization; and</span></div><div style="margin-top:5pt;padding-left:36pt;text-indent:-18pt"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">fair value estimates of contingent consideration receivable or payable related to acquisitions or dispositions. </span></div><div style="margin-top:5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company believes these estimates are reasonable based on information currently available at the time they are made. The Company also considered potential impact of macroeconomic factors including inflation, volatility in interest rates, the war in Ukraine and COVID-19 to its customer base in various industries and geographies. Insurance exposures subject to variable factors are subject to mid-term and end of term adjustments, as well as policy audits, which may reduce premiums and corresponding commissions. Estimates were updated based on internal and industry specific economic data. Actual results may differ from these estimates</span><span style="color:#000000;font-family:'Calibri',sans-serif;font-size:11pt;font-weight:400;line-height:120%">.</span></div>
CY2022	mmc	Revenue From Contract With Customer Threshold Percentage Of Total Revenue RevenueFromContractWithCustomerThresholdPercentageOfTotalRevenue	0.02
CY2022	mmc	Brokerage Revenue Number Of Annual Installments BrokerageRevenueNumberOfAnnualInstallments	4	installment
CY2022Q4	us-gaap	Contract With Customer Asset Gross ContractWithCustomerAssetGross	335000000	usd
CY2021Q4	us-gaap	Contract With Customer Asset Gross ContractWithCustomerAssetGross	290000000	usd
CY2020Q4	us-gaap	Contract With Customer Asset Gross ContractWithCustomerAssetGross	236000000	usd
CY2022Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	837000000	usd
CY2021Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	776000000	usd
CY2020Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	676000000	usd
CY2021Q4	us-gaap	Contract With Customer Asset Gross ContractWithCustomerAssetGross	290000000	usd
CY2020Q4	us-gaap	Contract With Customer Asset Gross ContractWithCustomerAssetGross	236000000	usd
CY2022	us-gaap	Contract With Customer Asset Cumulative Catch Up Adjustment To Revenue Change In Measure Of Progress ContractWithCustomerAssetCumulativeCatchUpAdjustmentToRevenueChangeInMeasureOfProgress	661000000	usd
CY2021	us-gaap	Contract With Customer Asset Cumulative Catch Up Adjustment To Revenue Change In Measure Of Progress ContractWithCustomerAssetCumulativeCatchUpAdjustmentToRevenueChangeInMeasureOfProgress	547000000	usd
CY2022	us-gaap	Contract With Customer Asset Reclassified To Receivable ContractWithCustomerAssetReclassifiedToReceivable	-614000000	usd
CY2021	us-gaap	Contract With Customer Asset Reclassified To Receivable ContractWithCustomerAssetReclassifiedToReceivable	-493000000	usd
CY2022	mmc	Contract With Customer Asset Effect Of Foreign Exchange Rate Changes ContractWithCustomerAssetEffectOfForeignExchangeRateChanges	-2000000	usd
CY2021	mmc	Contract With Customer Asset Effect Of Foreign Exchange Rate Changes ContractWithCustomerAssetEffectOfForeignExchangeRateChanges	0	usd
CY2022Q4	us-gaap	Contract With Customer Asset Gross ContractWithCustomerAssetGross	335000000	usd
CY2021Q4	us-gaap	Contract With Customer Asset Gross ContractWithCustomerAssetGross	290000000	usd
CY2021Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	776000000	usd
CY2020Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	676000000	usd
CY2022	mmc	Contractwith Customer Liability Increase Decreasefor Cash Receivedfor Performance Obligations Not Yet Fulfilled ContractwithCustomerLiabilityIncreaseDecreaseforCashReceivedforPerformanceObligationsNotYetFulfilled	726000000	usd
CY2021	mmc	Contractwith Customer Liability Increase Decreasefor Cash Receivedfor Performance Obligations Not Yet Fulfilled ContractwithCustomerLiabilityIncreaseDecreaseforCashReceivedforPerformanceObligationsNotYetFulfilled	642000000	usd
CY2022	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	-640000000	usd
CY2021	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	-539000000	usd
CY2022	mmc	Contract With Customer Liability Effect Of Foreign Exchange Rate Changes ContractWithCustomerLiabilityEffectOfForeignExchangeRateChanges	-25000000	usd
CY2021	mmc	Contract With Customer Liability Effect Of Foreign Exchange Rate Changes ContractWithCustomerLiabilityEffectOfForeignExchangeRateChanges	-3000000	usd
CY2022Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	837000000	usd
CY2021Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	776000000	usd
CY2022	us-gaap	Contract With Customer Performance Obligation Satisfied In Previous Period ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod	83000000	usd
CY2021	us-gaap	Contract With Customer Performance Obligation Satisfied In Previous Period ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod	84000000	usd
CY2020	us-gaap	Contract With Customer Performance Obligation Satisfied In Previous Period ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod	97000000	usd
CY2022Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	99000000	usd
CY2022Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	63000000	usd
CY2022Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	42000000	usd
CY2022Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	18000000	usd
CY2022Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	9000000	usd
CY2022	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	1600000000	usd
CY2021	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	1500000000	usd
CY2020	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	1300000000	usd
CY2022	mmc	Business Combination Consideration Transferred Assets Acquired BusinessCombinationConsiderationTransferredAssetsAcquired	734000000	usd
CY2021	mmc	Business Combination Consideration Transferred Assets Acquired BusinessCombinationConsiderationTransferredAssetsAcquired	1697000000	usd
CY2020	mmc	Business Combination Consideration Transferred Assets Acquired BusinessCombinationConsiderationTransferredAssetsAcquired	929000000	usd
CY2022	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	24000000	usd
CY2021	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	0	usd
CY2020	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	0	usd
CY2022	mmc	Business Combination Consideration Transferred Fiduciary Liabilities Assumed BusinessCombinationConsiderationTransferredFiduciaryLiabilitiesAssumed	6000000	usd
CY2021	mmc	Business Combination Consideration Transferred Fiduciary Liabilities Assumed BusinessCombinationConsiderationTransferredFiduciaryLiabilitiesAssumed	18000000	usd
CY2020	mmc	Business Combination Consideration Transferred Fiduciary Liabilities Assumed BusinessCombinationConsiderationTransferredFiduciaryLiabilitiesAssumed	21000000	usd
CY2022	us-gaap	Business Combination Consideration Transferred Liabilities Incurred BusinessCombinationConsiderationTransferredLiabilitiesIncurred	49000000	usd
CY2021	us-gaap	Business Combination Consideration Transferred Liabilities Incurred BusinessCombinationConsiderationTransferredLiabilitiesIncurred	213000000	usd
CY2020	us-gaap	Business Combination Consideration Transferred Liabilities Incurred BusinessCombinationConsiderationTransferredLiabilitiesIncurred	78000000	usd
CY2022	mmc	Business Combination Consideration Transferred Noncontrolling Interests Assumed BusinessCombinationConsiderationTransferredNoncontrollingInterestsAssumed	5000000	usd
CY2021	mmc	Business Combination Consideration Transferred Noncontrolling Interests Assumed BusinessCombinationConsiderationTransferredNoncontrollingInterestsAssumed	64000000	usd
CY2020	mmc	Business Combination Consideration Transferred Noncontrolling Interests Assumed BusinessCombinationConsiderationTransferredNoncontrollingInterestsAssumed	0	usd
CY2022	mmc	Business Combination Fair Value Of Previously Held Equity Method Investment BusinessCombinationFairValueOfPreviouslyHeldEquityMethodInvestment	6000000	usd
CY2021	mmc	Business Combination Fair Value Of Previously Held Equity Method Investment BusinessCombinationFairValueOfPreviouslyHeldEquityMethodInvestment	390000000	usd
CY2020	mmc	Business Combination Fair Value Of Previously Held Equity Method Investment BusinessCombinationFairValueOfPreviouslyHeldEquityMethodInvestment	0	usd
CY2022	mmc	Business Combination Contingentand Deferred Consideration BusinessCombinationContingentandDeferredConsideration	120000000	usd
CY2021	mmc	Business Combination Contingentand Deferred Consideration BusinessCombinationContingentandDeferredConsideration	153000000	usd
CY2020	mmc	Business Combination Contingentand Deferred Consideration BusinessCombinationContingentandDeferredConsideration	183000000	usd
CY2022	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	572000000	usd
CY2021	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	859000000	usd
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	647000000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	431000000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	441000000	usd
CY2020	us-gaap	Interest Paid Net InterestPaidNet	481000000	usd
CY2022	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1049000000	usd
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1069000000	usd
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	673000000	usd
CY2022	mmc	Paymentof Contingent Consideration PaymentofContingentConsideration	38000000	usd
CY2021	mmc	Paymentof Contingent Consideration PaymentofContingentConsideration	49000000	usd
CY2020	mmc	Paymentof Contingent Consideration PaymentofContingentConsideration	48000000	usd
CY2022	mmc	Proceeds From Contingent Consideration Prior Period Dispositions ProceedsFromContingentConsiderationPriorPeriodDispositions	0	usd
CY2021	mmc	Proceeds From Contingent Consideration Prior Period Dispositions ProceedsFromContingentConsiderationPriorPeriodDispositions	19000000	usd
CY2020	mmc	Proceeds From Contingent Consideration Prior Period Dispositions ProceedsFromContingentConsiderationPriorPeriodDispositions	0	usd
CY2022	mmc	Fair Value Measurementwith Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Includedin Earnings Net FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedinEarningsNet	-49000000	usd
CY2021	mmc	Fair Value Measurementwith Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Includedin Earnings Net FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedinEarningsNet	-57000000	usd
CY2020	mmc	Fair Value Measurementwith Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Includedin Earnings Net FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedinEarningsNet	-26000000	usd
CY2022	mmc	Adjustments And Payments Related To Contingent Consideration AdjustmentsAndPaymentsRelatedToContingentConsideration	-11000000	usd
CY2021	mmc	Adjustments And Payments Related To Contingent Consideration AdjustmentsAndPaymentsRelatedToContingentConsideration	-27000000	usd
CY2020	mmc	Adjustments And Payments Related To Contingent Consideration AdjustmentsAndPaymentsRelatedToContingentConsideration	22000000	usd
CY2022	mmc	Payments For Previous Acquisition Contingent Consideration PaymentsForPreviousAcquisitionContingentConsideration	32000000	usd
CY2021	mmc	Payments For Previous Acquisition Contingent Consideration PaymentsForPreviousAcquisitionContingentConsideration	28000000	usd
CY2020	mmc	Payments For Previous Acquisition Contingent Consideration PaymentsForPreviousAcquisitionContingentConsideration	54000000	usd
CY2022	mmc	Payments For Previous Acquisition Deferred Consideration PaymentsForPreviousAcquisitionDeferredConsideration	126000000	usd
CY2021	mmc	Payments For Previous Acquisition Deferred Consideration PaymentsForPreviousAcquisitionDeferredConsideration	89000000	usd
CY2020	mmc	Payments For Previous Acquisition Deferred Consideration PaymentsForPreviousAcquisitionDeferredConsideration	68000000	usd
CY2022	mmc	Payments For Previous Acquisition Deferredand Contingent Consideration PaymentsForPreviousAcquisitionDeferredandContingentConsideration	158000000	usd
CY2021	mmc	Payments For Previous Acquisition Deferredand Contingent Consideration PaymentsForPreviousAcquisitionDeferredandContingentConsideration	117000000	usd
CY2020	mmc	Payments For Previous Acquisition Deferredand Contingent Consideration PaymentsForPreviousAcquisitionDeferredandContingentConsideration	122000000	usd
CY2022	mmc	Proceeds From Previous Disposition Contingent Consideration ProceedsFromPreviousDispositionContingentConsideration	3000000	usd
CY2021	mmc	Proceeds From Previous Disposition Contingent Consideration ProceedsFromPreviousDispositionContingentConsideration	71000000	usd
CY2020	mmc	Proceeds From Previous Disposition Contingent Consideration ProceedsFromPreviousDispositionContingentConsideration	0	usd
CY2022	us-gaap	Stock Issued1 StockIssued1	372000000	usd
CY2021	us-gaap	Stock Issued1 StockIssued1	228000000	usd
CY2020	us-gaap	Stock Issued1 StockIssued1	219000000	usd
CY2022	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	367000000	usd
CY2021	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	348000000	usd
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	290000000	usd
CY2021Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	166000000	usd
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	142000000	usd
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	140000000	usd
CY2022	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	17000000	usd
CY2021	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	46000000	usd
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	47000000	usd
CY2022	mmc	Allowance For Doubtful Accounts Receivable Writeoffs Net Of Recoveries AllowanceForDoubtfulAccountsReceivableWriteoffsNetOfRecoveries	17000000	usd
CY2021	mmc	Allowance For Doubtful Accounts Receivable Writeoffs Net Of Recoveries AllowanceForDoubtfulAccountsReceivableWriteoffsNetOfRecoveries	16000000	usd
CY2020	mmc	Allowance For Doubtful Accounts Receivable Writeoffs Net Of Recoveries AllowanceForDoubtfulAccountsReceivableWriteoffsNetOfRecoveries	30000000	usd
CY2022	mmc	Allowance For Doubtful Accounts Receivable Effect Of Exchange Rate Changes And Other AllowanceForDoubtfulAccountsReceivableEffectOfExchangeRateChangesAndOther	-6000000	usd
CY2021	mmc	Allowance For Doubtful Accounts Receivable Effect Of Exchange Rate Changes And Other AllowanceForDoubtfulAccountsReceivableEffectOfExchangeRateChangesAndOther	-6000000	usd
CY2020	mmc	Allowance For Doubtful Accounts Receivable Effect Of Exchange Rate Changes And Other AllowanceForDoubtfulAccountsReceivableEffectOfExchangeRateChangesAndOther	-15000000	usd
CY2022Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	160000000	usd
CY2021Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	166000000	usd
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	142000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-849000000	usd
CY2022	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-110000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-739000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	376000000	usd
CY2021	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-159000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	535000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-557000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	182000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-739000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	840000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	305000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	535000000	usd
CY2020	mmc	Other Comprehensive Income Loss Adjustment From Mergerof Pension Plans Pensionand Postretirement Benefit Plans Before Tax OtherComprehensiveIncomeLossAdjustmentFromMergerofPensionPlansPensionandPostretirementBenefitPlansBeforeTax	-11000000	usd
CY2020	mmc	Other Comprehensive Income Loss Adjustment From Mergerof Pension Plans Pensionand Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossAdjustmentFromMergerofPensionPlansPensionandOtherPostretirementBenefitPlansTax	-2000000	usd
CY2020	mmc	Other Comprehensive Income Loss Adjustment From Mergerof Pension Plans Pensionand Other Postretirement Benefit Plans Netof Tax OtherComprehensiveIncomeLossAdjustmentFromMergerofPensionPlansPensionandOtherPostretirementBenefitPlansNetofTax	-9000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-225000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-170000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-55000000	usd
CY2022Q4	mmc	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-8000000	usd
CY2021Q4	mmc	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	13000000	usd
CY2022Q4	mmc	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Adjustment Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansAdjustmentTax	1340000000	usd
CY2021Q4	mmc	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Adjustment Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansAdjustmentTax	1501000000	usd
CY2022	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	705000000	usd
CY2022	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	579000000	usd
CY2022	mmc	Business Combination Contingentand Deferred Consideration BusinessCombinationContingentandDeferredConsideration	120000000	usd
CY2022	us-gaap	Finitelived Intangible Assets Acquired1 FinitelivedIntangibleAssetsAcquired1	228000000	usd
CY2022	us-gaap	Business Combination Pro Forma Information Revenue Of Acquiree Since Acquisition Date Actual BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual	58000000	usd
CY2022	us-gaap	Business Combination Pro Forma Information Earnings Or Loss Of Acquiree Since Acquisition Date Actual BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual	-5000000	usd
CY2021	us-gaap	Business Combination Pro Forma Information Revenue Of Acquiree Since Acquisition Date Actual BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual	114000000	usd
CY2021	us-gaap	Business Combination Pro Forma Information Earnings Or Loss Of Acquiree Since Acquisition Date Actual BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual	3000000	usd
CY2020	us-gaap	Business Combination Pro Forma Information Revenue Of Acquiree Since Acquisition Date Actual BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual	169000000	usd
CY2020	us-gaap	Business Combination Pro Forma Information Earnings Or Loss Of Acquiree Since Acquisition Date Actual BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual	11000000	usd
CY2022Q4	mmc	Cash And Cash Equivalents Held In A Fiduciary Capacity CashAndCashEquivalentsHeldInAFiduciaryCapacity	36000000	usd
CY2022Q1	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	-39000000	usd
CY2021	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	1400000000	usd
CY2021	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	888000000	usd
CY2021	mmc	Business Combination Contingentand Deferred Consideration BusinessCombinationContingentandDeferredConsideration	153000000	usd
CY2021	mmc	Business Combination Fair Value Of Previously Held Equity Method Investment BusinessCombinationFairValueOfPreviouslyHeldEquityMethodInvestment	390000000	usd
CY2022	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	20880000000	usd
CY2021	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	20220000000	usd
CY2020	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	17586000000	usd
CY2022	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	3078000000	usd
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CY2020	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	2042000000	usd
CY2022	us-gaap	Business Acquisition Pro Forma Earnings Per Share Basic BusinessAcquisitionProFormaEarningsPerShareBasic	6.16
CY2021	us-gaap	Business Acquisition Pro Forma Earnings Per Share Basic BusinessAcquisitionProFormaEarningsPerShareBasic	6.27
CY2020	us-gaap	Business Acquisition Pro Forma Earnings Per Share Basic BusinessAcquisitionProFormaEarningsPerShareBasic	4.03
CY2022	us-gaap	Business Acquisition Pro Forma Earnings Per Share Diluted BusinessAcquisitionProFormaEarningsPerShareDiluted	6.10
CY2021	us-gaap	Business Acquisition Pro Forma Earnings Per Share Diluted BusinessAcquisitionProFormaEarningsPerShareDiluted	6.20
CY2020	us-gaap	Business Acquisition Pro Forma Earnings Per Share Diluted BusinessAcquisitionProFormaEarningsPerShareDiluted	3.99
CY2021Q4	us-gaap	Goodwill Goodwill	16317000000	usd
CY2020Q4	us-gaap	Goodwill Goodwill	15517000000	usd
CY2022	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	460000000	usd
CY2021	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	1045000000	usd
CY2022	us-gaap	Goodwill Other Increase Decrease GoodwillOtherIncreaseDecrease	-526000000	usd
CY2021	us-gaap	Goodwill Other Increase Decrease GoodwillOtherIncreaseDecrease	-245000000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	16251000000	usd
CY2021Q4	us-gaap	Goodwill Goodwill	16317000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	4353000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1816000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	2537000000	usd
CY2021Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	4431000000	usd
CY2021Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1621000000	usd
CY2021Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	2810000000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	338000000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	365000000	usd
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	351000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	327000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	307000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	274000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	253000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	249000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	1127000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	2537000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	1468000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	1590000000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	1075000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	2614000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	2618000000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	1718000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	4082000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	4208000000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	2793000000	usd
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	262000000	usd
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	251000000	usd
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	172000000	usd
CY2022	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	653000000	usd
CY2021	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	714000000	usd
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	456000000	usd
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	123000000	usd
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	132000000	usd
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	79000000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1038000000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1097000000	usd
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	707000000	usd
CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	38000000	usd
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-40000000	usd
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CY2021	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-12000000	usd
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CY2022	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	10000000	usd
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-11000000	usd
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CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-63000000	usd
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CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	995000000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1034000000	usd
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CY2022Q4	mmc	Deferred Tax Assets Tax Deferred Expense Reservesand Accruals Netof Valuation Allowance DeferredTaxAssetsTaxDeferredExpenseReservesandAccrualsNetofValuationAllowance	670000000	usd
CY2021Q4	mmc	Deferred Tax Assets Tax Deferred Expense Reservesand Accruals Netof Valuation Allowance DeferredTaxAssetsTaxDeferredExpenseReservesandAccrualsNetofValuationAllowance	647000000	usd
CY2022Q4	mmc	Deferred Tax Assets Operating Loss Carryforwards Foreign Netof Valuation Allowance DeferredTaxAssetsOperatingLossCarryforwardsForeignNetofValuationAllowance	275000000	usd
CY2021Q4	mmc	Deferred Tax Assets Operating Loss Carryforwards Foreign Netof Valuation Allowance DeferredTaxAssetsOperatingLossCarryforwardsForeignNetofValuationAllowance	293000000	usd
CY2022Q4	mmc	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions And Postretirement Benefits Netof Valuation Allowance DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensionsAndPostretirementBenefitsNetofValuationAllowance	172000000	usd
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CY2022Q4	mmc	Deferred Tax Assets Operating Loss Carryforwards Domestic Net Of Valuation Allowance DeferredTaxAssetsOperatingLossCarryforwardsDomesticNetOfValuationAllowance	285000000	usd
CY2021Q4	mmc	Deferred Tax Assets Operating Loss Carryforwards Domestic Net Of Valuation Allowance DeferredTaxAssetsOperatingLossCarryforwardsDomesticNetOfValuationAllowance	183000000	usd
CY2022Q4	mmc	Deferred Tax Assets Deferred Income Net Of Valuation Allowance DeferredTaxAssetsDeferredIncomeNetOfValuationAllowance	34000000	usd
CY2021Q4	mmc	Deferred Tax Assets Deferred Income Net Of Valuation Allowance DeferredTaxAssetsDeferredIncomeNetOfValuationAllowance	29000000	usd
CY2022Q4	mmc	Deferred Tax Assets Tax Deferred Expense Other Net Of Valuation Allowance DeferredTaxAssetsTaxDeferredExpenseOtherNetOfValuationAllowance	25000000	usd
CY2021Q4	mmc	Deferred Tax Assets Tax Deferred Expense Other Net Of Valuation Allowance DeferredTaxAssetsTaxDeferredExpenseOtherNetOfValuationAllowance	32000000	usd
CY2022Q4	mmc	Deferred Tax Assets Net Net Of Valuation Allowance DeferredTaxAssetsNetNetOfValuationAllowance	1461000000	usd
CY2021Q4	mmc	Deferred Tax Assets Net Net Of Valuation Allowance DeferredTaxAssetsNetNetOfValuationAllowance	1477000000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	543000000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	624000000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	510000000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	506000000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Reserves And Accruals DeferredTaxLiabilitiesDeferredExpenseReservesAndAccruals	408000000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Reserves And Accruals DeferredTaxLiabilitiesDeferredExpenseReservesAndAccruals	403000000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	107000000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	98000000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	57000000	usd
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CY2022Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	1625000000	usd
CY2021Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	1663000000	usd
CY2022Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	830000000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2022	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.027
CY2021	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.023
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.025
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.007
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.001
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.023
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0.026
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0
CY2022	mmc	Effective Income Tax Rate Reconciliation Gain On Deconsolidation Of Business Percent EffectiveIncomeTaxRateReconciliationGainOnDeconsolidationOfBusinessPercent	0
CY2021	mmc	Effective Income Tax Rate Reconciliation Gain On Deconsolidation Of Business Percent EffectiveIncomeTaxRateReconciliationGainOnDeconsolidationOfBusinessPercent	-0.015
CY2020	mmc	Effective Income Tax Rate Reconciliation Gain On Deconsolidation Of Business Percent EffectiveIncomeTaxRateReconciliationGainOnDeconsolidationOfBusinessPercent	0
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.007
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CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies EffectiveIncomeTaxRateReconciliationTaxContingencies	0.001
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CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.012
CY2022	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.244
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CY2022	mmc	Operating Loss Carryforwards Percentage Subjectto Expiration OperatingLossCarryforwardsPercentageSubjecttoExpiration	0.14
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	94000000	usd
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CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.0079
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CY2021	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	19820000000	usd
CY2020	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	17224000000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	871000000	usd
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	847000000	usd
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	856000000	usd

Files In Submission

Name	View Source	Status
mmc-20221231_cal.xml	Edgar Link	unprocessable
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0000062709-23-000014-index.html	Edgar Link	pending
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FilingSummary.xml	Edgar Link	unprocessable
mmc-20221231_lab.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
mmc-20221231.htm	Edgar Link	pending
mmc-20221231.xsd	Edgar Link	pending
mmc-20221231_g1.jpg	Edgar Link	pending
mmc12312022ex_1045.htm	Edgar Link	pending
mmc12312022ex_1054.htm	Edgar Link	pending
mmc12312022ex_231.htm	Edgar Link	pending
mmc12312022ex_311.htm	Edgar Link	pending
mmc12312022ex_312.htm	Edgar Link	pending
mmc12312022ex_321.htm	Edgar Link	pending
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R1.htm	Edgar Link	pending
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mmc-20221231_def.xml	Edgar Link	unprocessable
mmc-20221231_pre.xml	Edgar Link	unprocessable
mmc-20221231_htm.xml	Edgar Link	completed
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report.css	Edgar Link	pending
Show.js	Edgar Link	pending

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$MMC
MARSH & MCLENNAN COMPANIES, INC. Stock $mmc

2023 Q1 Form 10-K Financial Statement

#000006270923000014 Filed on February 13, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MMC MARSH & MCLENNAN COMPANIES, INC. Stock $mmc

2023 Q1 Form 10-K Financial Statement

#000006270923000014 Filed on February 13, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MMC
MARSH & MCLENNAN COMPANIES, INC. Stock $mmc