$AJG
Arthur J. Gallagher & Co. Stock $ajg

$ajg Overview Financials Valuation SEC Filings Company Website

2018 Q3 Form 10-Q Financial Statement

#000119312518309015 Filed on October 26, 2018

Income Statement

Concept	2018 Q3	2017 Q3
Revenue	$1.779B	$1.594B
YoY Change	11.6%	7.52%
Cost Of Revenue	$1.312B	$1.166B
YoY Change	12.53%	8.31%
Gross Profit	$466.7M	$428.0M
YoY Change	9.04%	5.42%
Gross Profit Margin	26.24%	26.86%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$33.40M	$30.50M
YoY Change	9.51%	18.68%
% of Gross Profit	7.16%	7.13%
Operating Expenses	$227.7M	$209.0M
YoY Change	8.95%	10.23%
Operating Profit	$239.0M	$219.0M
YoY Change	9.13%	1.2%
Interest Expense	$36.70M	$31.40M
YoY Change	16.88%	10.18%
% of Operating Profit	15.36%	14.34%
Other Income/Expense, Net
YoY Change
Pretax Income	$90.30M	$76.90M
YoY Change	17.43%	-18.97%
Income Tax	-$48.10M	-$41.20M
% Of Pretax Income	-53.27%	-53.58%
Net Earnings	$127.6M	$111.0M
YoY Change	14.95%	-9.61%
Net Earnings / Revenue	7.17%	6.96%
Basic Earnings Per Share	$0.70	$0.61
Diluted Earnings Per Share	$0.68	$0.61
COMMON SHARES
Basic Shares Outstanding	183.3M shares	180.5M shares
Diluted Shares Outstanding

Balance Sheet

Concept	2018 Q3	2017 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$605.0M	$565.0M
YoY Change	7.08%	6.2%
Cash & Equivalents	$605.0M	$564.9M
Short-Term Investments
Other Short-Term Assets	$951.5M	$679.6M
YoY Change	40.01%	13.06%
Inventory
Prepaid Expenses	$99.90M	$89.00M
Receivables
Other Receivables
Total Short-Term Assets	$8.084B	$5.087B
YoY Change	58.9%	20.73%
LONG-TERM ASSETS
Property, Plant & Equipment	$429.3M	$413.4M
YoY Change	3.85%	93.27%
Goodwill	$4.501B	$4.160B
YoY Change	8.19%	10.57%
Intangibles	$1.772B	$1.671B
YoY Change	6.04%	2.53%
Long-Term Investments
YoY Change
Other Assets	$584.6M	$559.6M
YoY Change	4.47%	-11.23%
Total Long-Term Assets	$8.031B	$7.723B
YoY Change	3.98%	10.54%
TOTAL ASSETS
Total Short-Term Assets	$8.084B	$5.087B
Total Long-Term Assets	$8.031B	$7.723B
Total Assets	$16.11B	$12.81B
YoY Change	25.79%	14.38%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$5.694B	$3.509B
YoY Change	62.27%	22.39%
Accrued Expenses	$938.0M	$768.0M
YoY Change	22.14%	17.97%
Deferred Revenue
YoY Change
Short-Term Debt	$230.0M	$125.0M
YoY Change	84.0%	-79.44%
Long-Term Debt Due	$230.0M	$125.0M
YoY Change	84.0%	-79.44%
Total Short-Term Liabilities	$7.423B	$4.705B
YoY Change	57.75%	6.96%
LONG-TERM LIABILITIES
Long-Term Debt	$3.141B	$2.742B
YoY Change	14.57%	34.09%
Other Long-Term Liabilities	$862.1M	$1.191B
YoY Change	-27.63%	17.3%
Total Long-Term Liabilities	$4.003B	$3.933B
YoY Change	1.79%	28.52%
TOTAL LIABILITIES
Total Short-Term Liabilities	$7.423B	$4.705B
Total Long-Term Liabilities	$4.003B	$3.933B
Total Liabilities	$11.50B	$8.638B
YoY Change	33.15%	15.81%
SHAREHOLDERS EQUITY
Retained Earnings	$1.518B	$1.062B
YoY Change	42.89%	19.36%
Common Stock	$3.700B	$3.547B
YoY Change	4.33%	3.79%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$4.545B	$4.110B
YoY Change
Total Liabilities & Shareholders Equity	$16.11B	$12.81B
YoY Change	25.79%	14.38%

Cashflow Statement

Concept	2018 Q3	2017 Q3
OPERATING ACTIVITIES
Net Income	$127.6M	$111.0M
YoY Change	14.95%	-9.61%
Depreciation, Depletion And Amortization	$33.40M	$30.50M
YoY Change	9.51%	18.68%
Cash From Operating Activities	$191.3M	$332.3M
YoY Change	-42.43%	38.75%
INVESTING ACTIVITIES
Capital Expenditures	-$28.10M	-$28.20M
YoY Change	-0.35%	-21.01%
Acquisitions
YoY Change
Other Investing Activities	-$180.0M	-$90.60M
YoY Change	98.68%	62.37%
Cash From Investing Activities	-$208.1M	-$118.8M
YoY Change	75.17%	29.84%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-44.80M	-165.6M
YoY Change	-72.95%	549.41%
NET CHANGE
Cash From Operating Activities	191.3M	332.3M
Cash From Investing Activities	-208.1M	-118.8M
Cash From Financing Activities	-44.80M	-165.6M
Net Change In Cash	-61.60M	47.90M
YoY Change	-228.6%	-60.9%
FREE CASH FLOW
Cash From Operating Activities	$191.3M	$332.3M
Capital Expenditures	-$28.10M	-$28.20M
Free Cash Flow	$219.4M	$360.5M
YoY Change	-39.14%	31.0%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2017Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	564900000
CY2017Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2180500000
CY2017Q3	us-gaap	Restricted Cash Current RestrictedCashCurrent	1615600000
CY2017Q3	ajg	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingFairValue	9300000
CY2017Q3	ajg	Provisional Compensation Cash Award Approved For Future Grant By Compensation Committee Units ProvisionalCompensationCashAwardApprovedForFutureGrantByCompensationCommitteeUnits	199000	shares
CY2018Q3	us-gaap	Accounts Receivable Billed For Long Term Contracts Or Programs AccountsReceivableBilledForLongTermContractsOrPrograms	331900000
CY2018Q3	us-gaap	Assets Current AssetsCurrent	8084000000
CY2018Q3	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	3516600000
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-673400000
CY2018Q3	us-gaap	Assets Assets	16114700000
CY2018Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Noncurrent Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilities	88300000
CY2018Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Property Plant And Equipment BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment	6500000
CY2018Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Cash And Equivalents BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents	13700000
CY2018Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Other BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther	131800000
CY2018Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities	115600000
CY2018Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities	203900000
CY2018Q3	us-gaap	Capitalized Contract Cost Accumulated Amortization CapitalizedContractCostAccumulatedAmortization	240600000
CY2018Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets	922200000
CY2018Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther	400000
CY2018Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Noncurrent Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentAssets	9000000
CY2018Q3	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	58900000
CY2018Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Net BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet	718300000
CY2018Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	605000000
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2260500000
CY2018Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	183700000	shares
CY2018Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	183700000	shares
CY2018Q3	us-gaap	Common Stock Value CommonStockValue	183700000
CY2018Q3	us-gaap	Deferred Tax Assets Net Noncurrent DeferredTaxAssetsNetNoncurrent	743400000
CY2018Q3	us-gaap	Deferred Revenue Current DeferredRevenueCurrent	396600000
CY2018Q3	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	300000
CY2018Q3	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	4700000
CY2018Q3	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	4400000
CY2018Q3	us-gaap	Deferred Revenue DeferredRevenue	472700000
CY2018Q3	us-gaap	Deferred Revenue Noncurrent DeferredRevenueNoncurrent	76100000
CY2018Q3	us-gaap	Derivative Asset Notional Amount DerivativeAssetNotionalAmount	13900000
CY2018Q3	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	13600000
CY2018Q3	invest	Derivative Notional Amount DerivativeNotionalAmount	610200000
CY2018Q3	us-gaap	Derivative Liability Notional Amount DerivativeLiabilityNotionalAmount	9100000
CY2018Q3	us-gaap	Escrow Deposit EscrowDeposit	54000000
CY2018Q3	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	35200000
CY2018Q3	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	183652000	shares
CY2018Q3	us-gaap	Equity Method Investment Summarized Financial Information Assets EquityMethodInvestmentSummarizedFinancialInformationAssets	65100000
CY2018Q3	us-gaap	Finite Lived Trade Names Gross FiniteLivedTradeNamesGross	35500000
CY2018Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	235300000
CY2018Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	719200000
CY2018Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	212000000
CY2018Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	258800000
CY2018Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	275400000
CY2018Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	1772100000
CY2018Q3	us-gaap	Finite Lived Noncompete Agreements Gross FiniteLivedNoncompeteAgreementsGross	2800000
CY2018Q3	us-gaap	Goodwill Goodwill	4501300000
CY2018Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Remainder Of Fiscal Year FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear	71400000
CY2018Q3	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	1772100000
CY2018Q3	us-gaap	Liabilities Current LiabilitiesCurrent	7422600000
CY2018Q3	us-gaap	Liabilities Liabilities	11502000000
CY2018Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	16114700000
CY2018Q3	us-gaap	Minority Interest MinorityInterest	68200000
CY2018Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	3141200000
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CY2018Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	584600000
CY2018Q3	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	99900000
CY2018Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	862100000
CY2018Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	429300000
CY2018Q3	us-gaap	Premiums And Other Receivables Net PremiumsAndOtherReceivablesNet	4872000000
CY2018Q3	us-gaap	Restricted Cash Current RestrictedCashCurrent	1655500000
CY2018Q3	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	472700000
CY2018Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1517600000
CY2018Q3	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	72700000
CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice	52.10
CY2018Q3	us-gaap	Short Term Borrowings ShortTermBorrowings	230000000
CY2018Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4612700000
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CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber	6600000	shares
CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	2300000	shares
CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	42.59
CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	9100000	shares
CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	49.93
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CY2018Q3	ajg	Maximum Potential Earnout Payable MaximumPotentialEarnoutPayable	120500000
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CY2018Q3	ajg	Provisional Compensation Cash Award Approved For Future Grant By Compensation Committee Units ProvisionalCompensationCashAwardApprovedForFutureGrantByCompensationCommitteeUnits	269000	shares
CY2018Q3	ajg	Number Of Commercial Clean Coal Production Facilities NumberOfCommercialCleanCoalProductionFacilities	34	pure
CY2018Q3	ajg	Number Of Square Feet NumberOfSquareFeet	360000	sqft
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CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	45.27
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	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1200000	shares
	us-gaap	Adjustment For Amortization AdjustmentForAmortization	199000000
	us-gaap	Business Acquisition Pro Forma Earnings Per Share Basic BusinessAcquisitionProFormaEarningsPerShareBasic	2.33
	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	4904700000
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	us-gaap	Business Combination Separately Recognized Transactions Additional Disclosures Acquisition Cost Expensed BusinessCombinationSeparatelyRecognizedTransactionsAdditionalDisclosuresAcquisitionCostExpensed	15200000
	us-gaap	Business Acquisition Pro Forma Earnings Per Share Diluted BusinessAcquisitionProFormaEarningsPerShareDiluted	2.31
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	29000000
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	242900000
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.17
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	671200000
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	700200000
	us-gaap	Costs And Expenses CostsAndExpenses	4399000000
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	289200000
	us-gaap	Depreciation Depreciation	90200000
	us-gaap	Derivative Instruments Gain Loss Reclassified From Accumulated Oci Into Income Effective Portion Net DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet	-5700000
	us-gaap	Derivative Net Hedge Ineffectiveness Gain Loss DerivativeNetHedgeIneffectivenessGainLoss	400000
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.26
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	98500000
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.28
	us-gaap	Foreign Currency Transaction Gain Loss Unrealized ForeignCurrencyTransactionGainLossUnrealized	-5400000
	us-gaap	Gain Loss On Investments GainLossOnInvestments	1800000
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	330600000
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-107800000
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	49000000
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	151100000
	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	24500000
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-800000
	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	6200000
	us-gaap	Interest Expense InterestExpense	92900000
	us-gaap	Increase Decrease In Reinsurance Payables IncreaseDecreaseInReinsurancePayables	755600000
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-13900000
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	15000000
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1800000	shares
	us-gaap	Interest Paid Net InterestPaidNet	90300000
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	2059200000
	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	89	Entity
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-402200000
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-46600000
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	593200000
	us-gaap	Net Income Loss NetIncomeLoss	409800000
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	28600000
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-3700000
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	10200000
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	11700000
	us-gaap	Operating Expenses OperatingExpenses	612700000
	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	246400000
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	5700000
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Reclassification Adjustment From Aoci Realized Upon Sale Or Liquidation Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationBeforeTax	0
	us-gaap	Payments For Previous Acquisition PaymentsForPreviousAcquisition	23100000
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	4100000
	ajg	Increase Decrease In Premiums And Fees Receivable IncreaseDecreaseInPremiumsAndFeesReceivable	800100000
	ajg	Payments To Acquire Businesses Net Of Cash And Restricted Cash Acquired PaymentsToAcquireBusinessesNetOfCashAndRestrictedCashAcquired	302700000
	ajg	Change In Estimated Acquisition Earnout Payables ChangeInEstimatedAcquisitionEarnoutPayables	27500000
	ajg	Share Based Compensation Arrangement By Share Based Payment Award Options Exercised In Period Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodIntrinsicValue	28300000
	ajg	Business Acquisitions Pro Forma Net Income Loss To Controlling Interest BusinessAcquisitionsProFormaNetIncomeLossToControllingInterest	421500000
	ajg	Proceeds From Settlements On Terminated Interest Rate Swaps ProceedsFromSettlementsOnTerminatedInterestRateSwaps	8300000
	ajg	Net Proceeds From Sales Of Operations NetProceedsFromSalesOfOperations	2900000
	ajg	Cost Reimbursements CostReimbursements	102100000
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	211600000
	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	8600000
	us-gaap	Payments For Capital Improvements PaymentsForCapitalImprovements	93800000
	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	26200000
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	50200000
	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	348000000
	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	3223000000
	us-gaap	Proceeds From Repayments Of Debt ProceedsFromRepaymentsOfDebt	18000000
	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	3426000000
	us-gaap	Profit Loss ProfitLoss	438400000
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4729600000
	us-gaap	Share Based Compensation ShareBasedCompensation	12900000
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y0M0D
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.028	pure
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.023	pure
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.272	pure
	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	12900000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	179800000	shares
	ajg	Amortization Of Deferred Compensation And Restricted Stock AmortizationOfDeferredCompensationAndRestrictedStock	25400000
	ajg	Earnout Payments For Acquisitions EarnoutPaymentsForAcquisitions	30300000
	ajg	Net Change In Accrued Compensation And Other Current Liabilities NetChangeInAccruedCompensationAndOtherCurrentLiabilities	7700000
	ajg	Weighted Average Number Of Common And Common Equivalent Shares Outstanding WeightedAverageNumberOfCommonAndCommonEquivalentSharesOutstanding	181600000	shares
	ajg	Increase Decrease In Premiums And Fee Receivable IncreaseDecreaseInPremiumsAndFeeReceivable	800100000
	ajg	Revenue From Contract With Customer Before Reimbursements Excluding Assessed Tax RevenueFromContractWithCustomerBeforeReimbursementsExcludingAssessedTax	4627500000
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	900000	shares
	us-gaap	Adjustment For Amortization AdjustmentForAmortization	214400000
	dei	Amendment Flag AmendmentFlag	false
	us-gaap	Business Acquisition Pro Forma Earnings Per Share Basic BusinessAcquisitionProFormaEarningsPerShareBasic	2.86
	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	5385800000
	us-gaap	Business Combination Consideration Transferred Equity Interests Issued And Issuable BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable	50700000
	us-gaap	Business Acquisition Equity Interests Issued Or Issuable Number Of Shares Issued BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued	778000	shares
	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	7300000
	dei	Document Type DocumentType	10-Q
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	us-gaap	Deferred Revenue Revenue Recognized1 DeferredRevenueRevenueRecognized1	312600000
	us-gaap	Deferred Revenue Additions DeferredRevenueAdditions	340900000
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	309200000
	us-gaap	Depreciation Depreciation	94800000
	us-gaap	Derivative Instruments Gain Loss Reclassified From Accumulated Oci Into Income Effective Portion Net DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet	4200000
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	227000000
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2018
	us-gaap	Derivatives Methods Of Accounting Hedge Effectiveness DerivativesMethodsOfAccountingHedgeEffectiveness	<div> <p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"> <b>Hedge Accounting</b></p> <p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt"> In August 2017, the FASB issued ASU <font style="WHITE-SPACE: nowrap">No. 2017-12,</font> Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities. The new guidance amends the hedge accounting model in the current guidance to enable entities to better portray the economics of their risk management activities in the financial statements and enhance the transparency and understandability of hedge results. The new guidance requires revised tabular disclosures that focus on the effect of hedge accounting by income statement line and the disclosure of the cumulative basis adjustments to the hedged assets and liabilities in fair value hedges. Certain additional disclosures are also required for hedge relationships designated under the <font style="WHITE-SPACE: nowrap"><font style="WHITE-SPACE: nowrap">last-of-layer</font></font> method. The current guidance that requires entities to disclose hedge ineffectiveness has been eliminated because this amount will no longer be separately measured. Under the new guidance, entities will apply the amendments to cash flow and net investment hedge relationships that exist on the date of adoption using a modified retrospective approach (i.e., with a cumulative effect adjustment recorded to the opening balance of retained earnings as of the initial application date). The new guidance also provides transition relief to make it easier for entities to apply certain amendments to existing hedges (including fair value hedges) where the hedge documentation needs to be modified. The presentation and disclosure requirements will be applied prospectively. The new guidance is effective for annual periods beginning after December 15, 2018, including interim periods within those periods. Early adoption is permitted in any interim period or annual year before the effective date. If the guidance is early adopted in an interim period, any adjustments would be reflected as of the beginning of the fiscal year that includes that interim period. We are currently assessing the impact that adopting this new guidance will have on our consolidated financial statements.</p> </div>
	us-gaap	Derivative Net Hedge Ineffectiveness Gain Loss DerivativeNetHedgeIneffectivenessGainLoss	-500000
	us-gaap	Business Combination Separately Recognized Transactions Additional Disclosures Acquisition Cost Expensed BusinessCombinationSeparatelyRecognizedTransactionsAdditionalDisclosuresAcquisitionCostExpensed	14500000
	us-gaap	Business Acquisition Pro Forma Earnings Per Share Diluted BusinessAcquisitionProFormaEarningsPerShareDiluted	2.81
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	28900000
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-44500000
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.23
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	407800000
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	436700000
	us-gaap	Costs And Expenses CostsAndExpenses	4840400000
	us-gaap	Gain Loss On Investments GainLossOnInvestments	8200000
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	436200000
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.78
	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210	pure
	dei	Entity Central Index Key EntityCentralIndexKey	0000354190
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-52100000
	dei	Entity Registrant Name EntityRegistrantName	GALLAGHER ARTHUR J & CO
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Document Period End Date DocumentPeriodEndDate	2018-09-30
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.83
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	-69600000
	us-gaap	Foreign Currency Transaction Gain Loss Unrealized ForeignCurrencyTransactionGainLossUnrealized	2000000
	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	404700000
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-111900000
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	50800000
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	168400000
	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	33000000
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	5700000
	us-gaap	Goodwill Purchase Accounting Adjustments GoodwillPurchaseAccountingAdjustments	1400000
	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	6700000
	us-gaap	Interest Expense InterestExpense	101900000
	us-gaap	Increase Decrease In Reinsurance Payables IncreaseDecreaseInReinsurancePayables	729100000
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	76800000
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	12900000
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	3300000	shares
	us-gaap	Interest Paid Net InterestPaidNet	98800000
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	2266200000
	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	-100000
	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	95	Entity
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-653800000
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	156800000
	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	27200000
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	504600000
	us-gaap	Net Income Loss NetIncomeLoss	516200000
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	31900000
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-2200000
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	4200000
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	0
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	0
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-116600000
	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	Segment
	us-gaap	Operating Expenses OperatingExpenses	666600000
	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	-113600000
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	1300000
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	4200000
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Reclassification Adjustment From Aoci Realized Upon Sale Or Liquidation Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationBeforeTax	0
	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	100000
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	11300000
	us-gaap	Payments For Capital Improvements PaymentsForCapitalImprovements	90800000
	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	560400000
	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	30900000
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	69900000
	us-gaap	Payments For Previous Acquisition PaymentsForPreviousAcquisition	62800000
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	3700000
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	226200000
	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	450000000
	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	2295000000
	us-gaap	Proceeds From Repayments Of Debt ProceedsFromRepaymentsOfDebt	19000000
	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	2355000000
	us-gaap	Profit Loss ProfitLoss	548100000
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	5276600000
	us-gaap	Share Based Compensation ShareBasedCompensation	10100000
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y6M0D
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P4Y18D
	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	37.55
	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	51500000
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.023	pure
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.027	pure
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P2Y7D
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	300000	shares
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.151	pure
	us-gaap	Use Of Estimates UseOfEstimates	<div> <p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt"> <b>Use of Estimates</b></p> <p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt"> The preparation of our consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. These accounting principles require us to make estimates and assumptions that affect the reported amounts of assets and liabilities and revenues and expenses, and the disclosure of contingent assets and liabilities at the date of our consolidated financial statements. We are also required to make certain judgments and estimates that affect the disclosed and recorded amounts of revenues and expenses related to the impact of the adoption of and accounting under Topic 606. We periodically evaluate our estimates and assumptions, including those relating to the valuation of goodwill and other intangible assets, investments (including our IRC Section 45 investments), income taxes, revenue recognition, deferred costs, stock-based compensation, claims handling obligations, retirement plans, litigation and contingencies. We base our estimates on historical experience and various assumptions that we believe to be reasonable based on specific circumstances. Such estimates and assumptions could change in the future as more information becomes known, which could impact the amounts reported and disclosed herein.</p> </div>
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	1300000	shares
	dei	Trading Symbol TradingSymbol	AJG
	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	49.10
	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	70.74
	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Lower Range Limit ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit	35.71
	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Upper Range Limit ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit	70.74
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1	P4Y8M12D
	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	10100000
	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	11300000
	us-gaap	Stock Issued During Period Shares Acquisitions StockIssuedDuringPeriodSharesAcquisitions	58200000	shares
	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	1400000	shares
	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	18400000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	182400000	shares
	ajg	Number Of Countries In Which Company Does Business Through Network Of Correspondent Brokers And Consultants NumberOfCountriesInWhichCompanyDoesBusinessThroughNetworkOfCorrespondentBrokersAndConsultants	150	Country
	ajg	Number Of Countries In Which Company Has Operations NumberOfCountriesInWhichCompanyHasOperations	34	Country
	ajg	Amortization Of Deferred Compensation And Restricted Stock AmortizationOfDeferredCompensationAndRestrictedStock	31700000
	ajg	Earnout Payments For Acquisitions EarnoutPaymentsForAcquisitions	56600000
	ajg	Deferred Revenue Additions Through Business Acquisitions DeferredRevenueAdditionsThroughBusinessAcquisitions	13800000
	ajg	Payments To Acquire Businesses Net Of Cash And Restricted Cash Acquired PaymentsToAcquireBusinessesNetOfCashAndRestrictedCashAcquired	575500000
	ajg	Change In Estimated Acquisition Earnout Payables ChangeInEstimatedAcquisitionEarnoutPayables	7200000
	ajg	Deferred Compensation And Restricted Stock Expenses Benefit DeferredCompensationAndRestrictedStockExpensesBenefit	6500000
	ajg	Amount Of Commitment Expiration Off Balance Sheet Commitments Within Year Two AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearTwo	200000
	ajg	Amount Of Commitment Expiration Off Balance Sheet Commitments Within Year Three AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearThree	200000
	ajg	Share Based Compensation Arrangement By Share Based Payment Award Options Exercised In Period Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodIntrinsicValue	47200000
	ajg	Business Acquisitions Pro Forma Net Income Loss To Controlling Interest BusinessAcquisitionsProFormaNetIncomeLossToControllingInterest	524000000
	ajg	Proceeds From Settlements On Terminated Interest Rate Swaps ProceedsFromSettlementsOnTerminatedInterestRateSwaps	2900000
	ajg	Amount Of Commitment Expiration Off Balance Sheet Commitments AmountOfCommitmentExpirationOffBalanceSheetCommitments	19400000
	ajg	Business Combination Aggregate Earnout Obligation Maximum BusinessCombinationAggregateEarnoutObligationMaximum	495700000
	ajg	Net Proceeds From Sales Of Operations NetProceedsFromSalesOfOperations	12600000
	ajg	Amount Of Commitment Expiration Off Balance Sheet Commitments Within Year Thereafter AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearThereafter	18600000
	ajg	Amount Of Commitment Expiration Off Balance Sheet Commitments Within Year One AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearOne
	ajg	Cost Reimbursements CostReimbursements	107500000
	ajg	Business Combination Aggregate Earnout Obligation Recorded Maximum BusinessCombinationAggregateEarnoutObligationRecordedMaximum	219600000
	ajg	Amount Of Commitment Expiration Off Balance Sheet Commitments Within Year Four AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearFour	200000
	ajg	Amount Of Commitment Expiration Off Balance Sheet Commitments Within Year Five AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearFive	200000
	ajg	Recorded Earn Out Payable RecordedEarnOutPayable	52800000
	ajg	Net Change In Accrued Compensation And Other Current Liabilities NetChangeInAccruedCompensationAndOtherCurrentLiabilities	56100000
	ajg	Weighted Average Number Of Common And Common Equivalent Shares Outstanding WeightedAverageNumberOfCommonAndCommonEquivalentSharesOutstanding	185700000	shares
	ajg	Deferred Equity Participation Plan Distributions To Key Executives Age DeferredEquityParticipationPlanDistributionsToKeyExecutivesAge	Age 62 (or the one-year anniversary of the date of the grant for participants over the age of 61 as of the grant date) or upon or after their actual retirement.
	ajg	Deferred Equity Participation Sub Plan Distributions Requisite Service Description DeferredEquityParticipationSubPlanDistributionsRequisiteServiceDescription	We annually make awards under sub-plans of the DEPP for certain production staff, which generally provide for vesting and/or distributions no sooner than five years from the date of awards, although certain awards vest and/or distribute after the earlier of fifteen years or the participant reaching age 65.
	ajg	Deferred Equity Participation Sub Plan Distributions To Key Executives Age DeferredEquityParticipationSubPlanDistributionsToKeyExecutivesAge	Age 65
	ajg	Description Of Contracts Renewal Period DescriptionOfContractsRenewalPeriod	One year or less.
	ajg	Operating Lease Commitment Expiration Date OperatingLeaseCommitmentExpirationDate	2018-02-28
	ajg	Number Of Employees NumberOfEmployees	2000	Employees
	ajg	Collateralized Delinquency Receivables Period CollateralizedDelinquencyReceivablesPeriod	P7D
	ajg	Weighted Average Period WeightedAveragePeriod	P4Y
	ajg	Acquired Property Through Lease Percentage AcquiredPropertyThroughLeasePercentage	0.60	pure
	ajg	Percentage Of Commissions And Fee Revenues Recongized On Effective Date Of Insurance Contract PercentageOfCommissionsAndFeeRevenuesRecongizedOnEffectiveDateOfInsuranceContract	0.70	pure
	ajg	Percentage Of Commissions And Fee Revenues Recongized In First Three Months Of Insurance Contract PercentageOfCommissionsAndFeeRevenuesRecongizedInFirstThreeMonthsOfInsuranceContract	0.20	pure
	ajg	Percentage Of Commissions And Fee Revenues Recongized After First Three Months Of Insurance Contract PercentageOfCommissionsAndFeeRevenuesRecongizedAfterFirstThreeMonthsOfInsuranceContract	0.10	pure
	ajg	Acquired Property Through Lease Area AcquiredPropertyThroughLeaseArea	306000	sqft
	ajg	Increase Decrease In Premiums And Fee Receivable IncreaseDecreaseInPremiumsAndFeeReceivable	782300000
	ajg	Revenue From Contract With Customer Before Reimbursements Excluding Assessed Tax RevenueFromContractWithCustomerBeforeReimbursementsExcludingAssessedTax	5169100000
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350	pure
	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	488	Entity
CY2017Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1700000	shares
CY2017Q3	us-gaap	Adjustment For Amortization AdjustmentForAmortization	69600000
CY2017Q3	us-gaap	Business Acquisition Pro Forma Earnings Per Share Basic BusinessAcquisitionProFormaEarningsPerShareBasic	0.62
CY2017Q3	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	1650200000
CY2017Q3	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	5700000
CY2017Q3	us-gaap	Business Combination Separately Recognized Transactions Additional Disclosures Acquisition Cost Expensed BusinessCombinationSeparatelyRecognizedTransactionsAdditionalDisclosuresAcquisitionCostExpensed	4900000
CY2017Q3	us-gaap	Business Acquisition Pro Forma Earnings Per Share Diluted BusinessAcquisitionProFormaEarningsPerShareDiluted	0.62
CY2017Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	5500000
CY2017Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.39
CY2017Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	273600000
CY2017Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	279100000
CY2017Q3	us-gaap	Costs And Expenses CostsAndExpenses	1516800000
CY2017Q3	us-gaap	Depreciation Depreciation	30500000
CY2017Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.61
CY2017Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.61
CY2017Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	76900000
CY2017Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-41200000
CY2017Q3	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	4500000
CY2017Q3	us-gaap	Interest Expense InterestExpense	31400000
CY2017Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	2000000	shares
CY2017Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	680500000
CY2017Q3	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	31	Entity
CY2017Q3	us-gaap	Net Income Loss NetIncomeLoss	111000000
CY2017Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	7100000
CY2017Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-1100000
CY2017Q3	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	2900000
CY2017Q3	us-gaap	Operating Expenses OperatingExpenses	209000000
CY2017Q3	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	157000000
CY2017Q3	us-gaap	Profit Loss ProfitLoss	118100000
CY2017Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1593700000
CY2017Q3	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	4400000
CY2017Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	180500000	shares
CY2017Q3	ajg	Change In Estimated Acquisition Earnout Payables ChangeInEstimatedAcquisitionEarnoutPayables	10600000
CY2017Q3	ajg	Business Acquisitions Pro Forma Net Income Loss To Controlling Interest BusinessAcquisitionsProFormaNetIncomeLossToControllingInterest	113000000
CY2017Q3	ajg	Cost Reimbursements CostReimbursements	33800000
CY2017Q3	ajg	Weighted Average Number Of Common And Common Equivalent Shares Outstanding WeightedAverageNumberOfCommonAndCommonEquivalentSharesOutstanding	182500000	shares
CY2017Q3	ajg	Revenue From Contract With Customer Before Reimbursements Excluding Assessed Tax RevenueFromContractWithCustomerBeforeReimbursementsExcludingAssessedTax	1559900000
CY2018Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1300000	shares
CY2018Q3	us-gaap	Adjustment For Amortization AdjustmentForAmortization	72800000
CY2018Q3	us-gaap	Business Acquisition Pro Forma Earnings Per Share Basic BusinessAcquisitionProFormaEarningsPerShareBasic	0.70
CY2018Q3	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	1780300000
CY2018Q3	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	1300000
CY2018Q3	us-gaap	Business Combination Separately Recognized Transactions Additional Disclosures Acquisition Cost Expensed BusinessCombinationSeparatelyRecognizedTransactionsAdditionalDisclosuresAcquisitionCostExpensed	4500000
CY2018Q3	us-gaap	Business Acquisition Pro Forma Earnings Per Share Diluted BusinessAcquisitionProFormaEarningsPerShareDiluted	0.68
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	11100000
CY2018Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.41
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	105300000
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	116400000
CY2018Q3	us-gaap	Costs And Expenses CostsAndExpenses	1688200000
CY2018Q3	us-gaap	Depreciation Depreciation	33400000
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.68
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.70
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	90300000
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-48100000
CY2018Q3	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	1100000
CY2018Q3	us-gaap	Interest Expense InterestExpense	36700000
CY2018Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	3500000	shares
CY2018Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	765700000
CY2018Q3	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	38	Entity
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	127600000
CY2018Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	10800000
CY2018Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-700000
CY2018Q3	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	2500000
CY2018Q3	us-gaap	Operating Expenses OperatingExpenses	227700000
CY2018Q3	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	-25200000
CY2018Q3	us-gaap	Profit Loss ProfitLoss	138400000
CY2018Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1778500000
CY2018Q3	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	3700000
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	183300000	shares
CY2018Q3	ajg	Change In Estimated Acquisition Earnout Payables ChangeInEstimatedAcquisitionEarnoutPayables	5800000
CY2018Q3	ajg	Business Acquisitions Pro Forma Net Income Loss To Controlling Interest BusinessAcquisitionsProFormaNetIncomeLossToControllingInterest	127500000
CY2018Q3	ajg	Business Combination Aggregate Earnout Obligation Maximum BusinessCombinationAggregateEarnoutObligationMaximum	495700000
CY2018Q3	ajg	Cost Reimbursements CostReimbursements	37300000
CY2018Q3	ajg	Business Combination Aggregate Earnout Obligation Recorded Maximum BusinessCombinationAggregateEarnoutObligationRecordedMaximum	219600000
CY2018Q3	ajg	Weighted Average Number Of Common And Common Equivalent Shares Outstanding WeightedAverageNumberOfCommonAndCommonEquivalentSharesOutstanding	186800000	shares
CY2018Q3	ajg	Revenue From Contract With Customer Before Reimbursements Excluding Assessed Tax RevenueFromContractWithCustomerBeforeReimbursementsExcludingAssessedTax	1741200000

Files In Submission

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0001193125-18-309015-index-headers.html	Edgar Link	pending
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ajg-20180930.xml	Edgar Link	completed
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2018 Q3 Form 10-Q Financial Statement

#000119312518309015 Filed on October 26, 2018

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AJG Arthur J. Gallagher & Co. Stock $ajg

2018 Q3 Form 10-Q Financial Statement

#000119312518309015 Filed on October 26, 2018

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AJG
Arthur J. Gallagher & Co. Stock $ajg