$AON
Aon plc Stock $aon

$aon Overview Financials Valuation SEC Filings Company Website

2012 Q4 Form 10-K Financial Statement

#000104746913001494 Filed on February 22, 2013

Income Statement

Concept	2012 Q4	2012 Q1	2011 Q4
Revenue	$3.115B	$2.841B	$2.994B
YoY Change	4.04%	2.97%	2.92%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin	$2.654B	$2.439B	$2.564B
YoY Change	3.51%	3.3%	3.85%
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$174.0M	$55.00M	$145.0M
YoY Change	20.0%	-61.81%	15.08%
% of Gross Profit
Operating Expenses	$2.653B	$2.439B	$2.564B
YoY Change	3.47%	3.3%	4.19%
Operating Profit	$461.0M	$402.0M	$430.0M
YoY Change	7.21%	1.01%
Interest Expense	-$50.00M	$59.00M	-$55.00M
YoY Change	-9.09%	-237.21%	12.24%
% of Operating Profit	-10.85%	14.68%	-12.79%
Other Income/Expense, Net	-$3.000M	$0.00	$9.000M
YoY Change	-133.33%	-100.0%	-131.03%
Pretax Income	$409.0M	$346.0M	$384.0M
YoY Change	6.51%	-2.81%	6.67%
Income Tax	$103.0M	$97.00M	$104.0M
% Of Pretax Income	25.18%	28.03%	27.08%
Net Earnings	$307.0M	$249.0M	$280.0M
YoY Change	9.64%	-2.35%	21.21%
Net Earnings / Revenue	9.86%	8.76%	9.35%
Basic Earnings Per Share	$0.95	$0.72	$0.85
Diluted Earnings Per Share	$0.93	$0.71	$0.83
COMMON SHARES
Basic Shares Outstanding		332.4M shares
Diluted Shares Outstanding		336.6M shares

Balance Sheet

Concept	2012 Q4	2012 Q1	2011 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$561.0M	$743.0M	$986.0M
YoY Change	-43.1%	-31.96%	-7.94%
Cash & Equivalents	$291.0M	$323.0M	$272.0M
Short-Term Investments	$346.0M	$510.0M	$785.0M
Other Short-Term Assets	$430.0M	$12.30B	$427.0M
YoY Change	0.7%	7.25%	-96.03%
Inventory
Prepaid Expenses	$231.0M
Receivables	$3.101B	$3.164B	$3.183B
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$16.38B	$16.21B	$15.51B
YoY Change	5.66%	6.55%	6.79%
LONG-TERM ASSETS
Property, Plant & Equipment	$820.0M	$808.0M	$783.0M
YoY Change	4.73%	2.15%	0.26%
Goodwill	$8.943B		$8.770B
YoY Change	1.97%		1.42%
Intangibles	$4.000B		$4.300B
YoY Change	-6.98%
Long-Term Investments	$102.0M	$211.0M	$164.0M
YoY Change	-37.8%	-33.65%	-47.44%
Other Assets	$916.0M	$946.0M	$721.0M
YoY Change	27.05%	-9.04%	-35.16%
Total Long-Term Assets	$13.82B	$14.06B	$13.79B
YoY Change	0.22%	-3.61%	-4.66%
TOTAL ASSETS
Total Short-Term Assets	$16.38B	$16.21B	$15.51B
Total Long-Term Assets	$13.82B	$14.06B	$13.79B
Total Assets	$30.49B	$30.27B	$29.55B
YoY Change	3.16%	1.57%	1.97%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$1.853B	$1.432B	$1.832B
YoY Change	1.15%	-7.25%	1.22%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$452.0M	$286.0M	$337.0M
YoY Change	34.12%	-43.03%	-31.5%
Total Short-Term Liabilities	$15.35B	$14.25B	$13.76B
YoY Change	11.56%	7.49%	6.26%
LONG-TERM LIABILITIES
Long-Term Debt	$3.713B	$4.168B	$4.155B
YoY Change	-10.64%	-5.47%	3.51%
Other Long-Term Liabilities	$1.036B	$3.435B	$1.024B
YoY Change	1.17%	-5.81%	-66.43%
Total Long-Term Liabilities	$4.749B	$7.603B	$5.179B
YoY Change	-8.3%	-5.62%	-26.68%
TOTAL LIABILITIES
Total Short-Term Liabilities	$15.35B	$14.25B	$13.76B
Total Long-Term Liabilities	$4.749B	$7.603B	$5.179B
Total Liabilities	$22.68B	$21.91B	$21.43B
YoY Change	5.83%	2.5%	3.38%
SHAREHOLDERS EQUITY
Retained Earnings	$5.933B		$8.594B
YoY Change	-30.96%
Common Stock	$4.439B		$4.407B
YoY Change	0.73%
Preferred Stock
YoY Change
Treasury Stock (at cost)			$2.553B
YoY Change
Treasury Stock Shares	0.000 shares		61.60M shares
Shareholders Equity	$7.762B	$8.358B	$8.078B
YoY Change
Total Liabilities & Shareholders Equity	$30.49B	$30.27B	$29.55B
YoY Change	3.16%	1.57%	1.97%

Cashflow Statement

Concept	2012 Q4	2012 Q1	2011 Q4
OPERATING ACTIVITIES
Net Income	$307.0M	$249.0M	$280.0M
YoY Change	9.64%	-2.35%	21.21%
Depreciation, Depletion And Amortization	$174.0M	$55.00M	$145.0M
YoY Change	20.0%	-61.81%	15.08%
Cash From Operating Activities	$552.0M	-$15.00M	$231.0M
YoY Change	138.96%	-109.68%	-2200.0%
INVESTING ACTIVITIES
Capital Expenditures	-$68.00M	$71.00M	-$90.00M
YoY Change	-24.44%	-226.79%	38.46%
Acquisitions		$23.00M
YoY Change
Other Investing Activities	$313.0M	$293.0M	-$103.0M
YoY Change	-403.88%	29.65%	-44.62%
Cash From Investing Activities	$245.0M	$222.0M	-$193.0M
YoY Change	-226.94%	30.59%	-23.11%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net		$100.0M
YoY Change
Debt Paid & Issued, Net		$140.0M
YoY Change
Cash From Financing Activities	-790.0M	-$166.0M	-87.00M
YoY Change	808.05%	-588.24%	-135.51%
NET CHANGE
Cash From Operating Activities	552.0M	-$15.00M	231.0M
Cash From Investing Activities	245.0M	$222.0M	-193.0M
Cash From Financing Activities	-790.0M	-$166.0M	-87.00M
Net Change In Cash	7.000M	$41.00M	-49.00M
YoY Change	-114.29%	-88.58%	188.24%
FREE CASH FLOW
Cash From Operating Activities	$552.0M	-$15.00M	$231.0M
Capital Expenditures	-$68.00M	$71.00M	-$90.00M
Free Cash Flow	$620.0M	-$86.00M	$321.0M
YoY Change	93.15%	-140.76%	494.44%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2012	us-gaap	Goodwill Translation Adjustments GoodwillTranslationAdjustments	84000000	USD
CY2012	us-gaap	Goodwill Allocation Adjustment GoodwillAllocationAdjustment	-6000000	USD
CY2012Q2	aon	Right To Receive Number Of Common Stock In Redomestication RightToReceiveNumberOfCommonStockInRedomestication	1	shares
CY2012Q2	aon	Right To Receive Common Stock In Redomestication Nominal Value Per Share RightToReceiveCommonStockInRedomesticationNominalValuePerShare	0.01
CY2012Q4	aon	Restricted Cash Operating Funds RestrictedCashOperatingFunds	77000000	GBP
CY2012Q4	aon	Restricted Cash Operating Funds RestrictedCashOperatingFunds	124000000	USD
CY2011Q4	aon	Restricted Cash Operating Funds RestrictedCashOperatingFunds	120000000	USD
CY2012Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	76000000	USD
CY2011Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	71000000	USD
CY2012Q4	aon	Fiduciary Assets Premium Trust Balances FiduciaryAssetsPremiumTrustBalances	4000000000	USD
CY2011Q4	aon	Fiduciary Assets Premium Trust Balances FiduciaryAssetsPremiumTrustBalances	4200000000	USD
CY2012Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	118000000	USD
CY2011Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	104000000	USD
CY2012	us-gaap	Restructuring Reserve Settled Without Cash RestructuringReserveSettledWithoutCash	1000000	USD
CY2011	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	30000000	USD
CY2010	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-7000000	USD
CY2012	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-19000000	USD
CY2011	us-gaap	Derivative Instruments Gain Loss Recognized In Income Net DerivativeInstrumentsGainLossRecognizedInIncomeNet	-20000000	USD
CY2010	us-gaap	Derivative Instruments Gain Loss Recognized In Income Net DerivativeInstrumentsGainLossRecognizedInIncomeNet	-11000000	USD
CY2012	us-gaap	Derivative Instruments Gain Loss Recognized In Income Net DerivativeInstrumentsGainLossRecognizedInIncomeNet	3000000	USD
CY2012	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	1000000	USD
CY2012	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	96000000	USD
CY2010	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	-2000000	USD
CY2012	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	1000000	USD
CY2010	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	-4000000	USD
CY2011	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-19000000	USD
CY2010	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-8000000	USD
CY2012	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	2000000	USD
CY2012	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	13000000	USD
CY2011	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	7000000	USD
CY2010	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	18000000	USD
CY2012	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	7000000	USD
CY2011	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	18000000	USD
CY2011	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	1000000	USD
CY2010	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	4000000	USD
CY2012	us-gaap	Labor And Related Expense LaborAndRelatedExpense	6709000000	USD
CY2011	us-gaap	Labor And Related Expense LaborAndRelatedExpense	6567000000	USD
CY2010	us-gaap	Labor And Related Expense LaborAndRelatedExpense	5097000000	USD
CY2011Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	1971000000	USD
CY2011Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1188000000	USD
CY2012Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	291000000	USD
CY2012	aon	Other General Expenses OtherGeneralExpenses	3209000000	USD
CY2012Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	2189000000	USD
CY2012Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1369000000	USD
CY2011Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	272000000	USD
CY2011	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	220000000	USD
CY2010	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	151000000	USD
CY2012	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	232000000	USD
CY2012Q4	us-gaap	Business Acquisition Cost Of Acquired Entity Purchase Price BusinessAcquisitionCostOfAcquiredEntityPurchasePrice	175000000	USD
CY2011Q4	us-gaap	Business Acquisition Cost Of Acquired Entity Purchase Price BusinessAcquisitionCostOfAcquiredEntityPurchasePrice	103000000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	199000000	USD
CY2012	us-gaap	Operating Leases Rent Expense Sublease Rentals1 OperatingLeasesRentExpenseSubleaseRentals1	72000000	USD
CY2012Q4	us-gaap	Indefinite Lived Trademarks IndefiniteLivedTrademarks	1025000000	USD
CY2012Q4	us-gaap	Business Acquisition Purchase Price Allocation Goodwill Amount BusinessAcquisitionPurchasePriceAllocationGoodwillAmount	90000000	USD
CY2011Q4	us-gaap	Business Acquisition Purchase Price Allocation Goodwill Amount BusinessAcquisitionPurchasePriceAllocationGoodwillAmount	126000000	USD
CY2012Q4	aon	Business Acquisition Purchase Price Allocation Intangible Assets BusinessAcquisitionPurchasePriceAllocationIntangibleAssets	100000000	USD
CY2011Q4	aon	Business Acquisition Purchase Price Allocation Intangible Assets BusinessAcquisitionPurchasePriceAllocationIntangibleAssets	33000000	USD
CY2012Q4	us-gaap	Business Acquisition Purchase Price Allocation Noncurrent Assets BusinessAcquisitionPurchasePriceAllocationNoncurrentAssets	190000000	USD
CY2011Q4	us-gaap	Business Acquisition Purchase Price Allocation Noncurrent Assets BusinessAcquisitionPurchasePriceAllocationNoncurrentAssets	159000000	USD
CY2012	aon	Disposal Group Not Discontinued Operation Gain Loss On Disposal And Other DisposalGroupNotDiscontinuedOperationGainLossOnDisposalAndOther	1000000	USD
CY2010	aon	Disposal Group Not Discontinued Operation Gain Loss On Disposal And Other DisposalGroupNotDiscontinuedOperationGainLossOnDisposalAndOther	-4000000	USD
CY2011	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	77000000	USD
CY2011	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	2000000	USD
CY2011	us-gaap	Goodwill Allocation Adjustment GoodwillAllocationAdjustment	1000000	USD
CY2011	us-gaap	Goodwill Translation Adjustments GoodwillTranslationAdjustments	-3000000	USD
CY2012Q4	us-gaap	Short Term Investments ShortTermInvestments	346000000	USD
CY2010Q4	us-gaap	Goodwill Goodwill	8647000000	USD
CY2011Q4	us-gaap	Short Term Investments ShortTermInvestments	785000000	USD
CY2011Q4	us-gaap	Indefinite Lived Trademarks IndefiniteLivedTrademarks	1024000000	USD
CY2011Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	4242000000	USD
CY2011	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	454000000	USD
CY2010	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	372000000	USD
CY2012	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	464000000	USD
CY2011Q4	us-gaap	Assets Current AssetsCurrent	15505000000	USD
CY2012Q4	aon	Operating Leases Future Minimum Payments Due Net Of Sublease Rental Income Current OperatingLeasesFutureMinimumPaymentsDueNetOfSubleaseRentalIncomeCurrent	432000000	USD
CY2012Q4	aon	Fiduciary Assets Interest Bearing FiduciaryAssetsInterestBearing	4029000000	USD
CY2012Q4	aon	Operating Leases Future Minimum Payments Net Of Sublease Rentals Due In Two Years OperatingLeasesFutureMinimumPaymentsNetOfSubleaseRentalsDueInTwoYears	396000000	USD
CY2012Q4	us-gaap	Assets Current AssetsCurrent	16382000000	USD
CY2011Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	966000000	USD
CY2012Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	3101000000	USD
CY2011	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	362000000	USD
CY2011Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	3183000000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	4358000000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1383000000	USD
CY2012Q4	aon	Fiduciary Assets FiduciaryAssets	12214000000	USD
CY2012	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	423000000	USD
CY2010	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	154000000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	394000000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	343000000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	299000000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	251000000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	464000000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	1950000000	USD
CY2011	us-gaap	Restructuring Reserve Settled With Cash RestructuringReserveSettledWithCash	178000000	USD
CY2011	us-gaap	Restructuring Reserve Translation Adjustment RestructuringReserveTranslationAdjustment	8000000	USD
CY2011Q4	us-gaap	Restructuring Reserve RestructuringReserve	173000000	USD
CY2010Q4	us-gaap	Business Acquisition Purchase Price Allocation Liabilities Assumed BusinessAcquisitionPurchasePriceAllocationLiabilitiesAssumed	43000000	USD
CY2010	us-gaap	Restructuring Reserve Settled With Cash RestructuringReserveSettledWithCash	232000000	USD
CY2010	us-gaap	Restructuring Reserve Translation Adjustment RestructuringReserveTranslationAdjustment	-5000000	USD
CY2010Q4	us-gaap	Restructuring Reserve RestructuringReserve	237000000	USD
CY2009Q4	us-gaap	Restructuring Reserve RestructuringReserve	263000000	USD
CY2012	us-gaap	Restructuring Reserve Settled With Cash RestructuringReserveSettledWithCash	142000000	USD
CY2012	us-gaap	Restructuring Reserve Translation Adjustment RestructuringReserveTranslationAdjustment	10000000	USD
CY2012Q4	us-gaap	Restructuring Reserve RestructuringReserve	137000000	USD
CY2011Q4	aon	Fiduciary Assets FiduciaryAssets	10838000000	USD
CY2012Q4	us-gaap	Other Assets Current OtherAssetsCurrent	430000000	USD
CY2011Q4	aon	Fiduciary Assets Interest Bearing FiduciaryAssetsInterestBearing	4190000000	USD
CY2011Q4	us-gaap	Other Assets Current OtherAssetsCurrent	427000000	USD
CY2011Q4	aon	Investments And Cash And Cash Equivalents InvestmentsAndCashAndCashEquivalents	5486000000	USD
CY2012Q4	aon	Operating Leases Future Minimum Payments Net Of Sublease Rental Income Due In Three Years OperatingLeasesFutureMinimumPaymentsNetOfSubleaseRentalIncomeDueInThreeYears	365000000	USD
CY2012Q4	us-gaap	Goodwill Goodwill	8943000000	USD
CY2012	us-gaap	Operating Income Loss OperatingIncomeLoss	1596000000	USD
CY2012Q4	aon	Operating Leases Future Minimum Payments Net Of Sublease Rental Income Due In Four Years OperatingLeasesFutureMinimumPaymentsNetOfSubleaseRentalIncomeDueInFourYears	332000000	USD
CY2011	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	525000000	USD
CY2012	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.240	pure
CY2012Q4	aon	Investments And Cash And Cash Equivalents InvestmentsAndCashAndCashEquivalents	4831000000	USD
CY2011Q4	us-gaap	Equity Method Investments EquityMethodInvestments	164000000	USD
CY2011Q4	us-gaap	Other Long Term Investments OtherLongTermInvestments	60000000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Securities Noncurrent AvailableForSaleSecuritiesDebtSecuritiesNoncurrent	15000000	USD
CY2012Q4	us-gaap	Equity Method Investments EquityMethodInvestments	102000000	USD
CY2012Q4	us-gaap	Other Long Term Investments OtherLongTermInvestments	43000000	USD
CY2011Q4	us-gaap	Goodwill Goodwill	8770000000	USD
CY2012Q4	us-gaap	Available For Sale Securities Debt Securities Noncurrent AvailableForSaleSecuritiesDebtSecuritiesNoncurrent	20000000	USD
CY2010	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	429000000	USD
CY2012	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	536000000	USD
CY2011	us-gaap	Operating Leases Rent Expense Sublease Rentals1 OperatingLeasesRentExpenseSubleaseRentals1	71000000	USD
CY2010	us-gaap	Operating Leases Rent Expense Sublease Rentals1 OperatingLeasesRentExpenseSubleaseRentals1	57000000	USD
CY2012Q4	aon	Operating Leases Future Minimum Payments Net Of Sublease Rental Income Due In Five Years OperatingLeasesFutureMinimumPaymentsNetOfSubleaseRentalIncomeDueInFiveYears	293000000	USD
CY2012Q4	aon	Operating Leases Future Minimum Payments Net Of Sublease Rental Income Due Thereafter OperatingLeasesFutureMinimumPaymentsNetOfSubleaseRentalIncomeDueThereafter	1072000000	USD
CY2012Q4	aon	Operating Leases Future Minimum Payments Net Of Sublease Rental Income Due OperatingLeasesFutureMinimumPaymentsNetOfSubleaseRentalIncomeDue	2890000000	USD
CY2011	aon	Other General Expenses OtherGeneralExpenses	3124000000	USD
CY2010	aon	Other General Expenses OtherGeneralExpenses	2171000000	USD
CY2012	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	455000000	USD
CY2011	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	235000000	USD
CY2010	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	228000000	USD
CY2012	us-gaap	Costs And Expenses CostsAndExpenses	9918000000	USD
CY2012	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-95000000	USD
CY2011	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	143000000	USD
CY2010	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	72000000	USD
CY2011	us-gaap	Costs And Expenses CostsAndExpenses	9691000000	USD
CY2010	us-gaap	Costs And Expenses CostsAndExpenses	7268000000	USD
CY2011	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.273	pure
CY2012Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	13000000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	17000000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	77000000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	100000000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1422000000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1695000000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	154000000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	219000000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	1268000000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	1476000000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Tax Deferred Income DeferredTaxLiabilitiesTaxDeferredIncome	30000000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities Tax Deferred Income DeferredTaxLiabilitiesTaxDeferredIncome	83000000	USD
CY2012Q4	aon	Deferred Tax Liabilities Other Accrued Expenses DeferredTaxLiabilitiesOtherAccruedExpenses	62000000	USD
CY2011Q4	aon	Deferred Tax Liabilities Other Accrued Expenses DeferredTaxLiabilitiesOtherAccruedExpenses	121000000	USD
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CY2011	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-186000000	USD
CY2010	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2539000000	USD
CY2012	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1125000000	USD
CY2011	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	828000000	USD
CY2010	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	250000000	USD
CY2010	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	180000000	USD
CY2012	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	118000000	USD
CY2011	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	201000000	USD
CY2010	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	194000000	USD
CY2012	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	733000000	USD
CY2011	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1673000000	USD
CY2010	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	2905000000	USD
CY2012	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	1077000000	USD
CY2011	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	1688000000	USD
CY2010	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	816000000	USD
CY2012	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	204000000	USD
CY2011	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	200000000	USD
CY2010	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	175000000	USD
CY2012	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	27000000	USD
CY2011	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	30000000	USD
CY2010	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	20000000	USD
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CY2010	us-gaap	Depreciation Depreciation	151000000	USD
CY2012	us-gaap	Adjustment For Amortization AdjustmentForAmortization	423000000	USD
CY2010	us-gaap	Adjustment For Amortization AdjustmentForAmortization	154000000	USD
CY2012	us-gaap	Share Based Compensation ShareBasedCompensation	212000000	USD
CY2010	us-gaap	Share Based Compensation ShareBasedCompensation	221000000	USD
CY2012	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-95000000	USD
CY2010	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	76000000	USD
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CY2009Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	217000000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Net Noncurrent DeferredTaxAssetsNetNoncurrent	258000000	USD
CY2010Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	346000000	USD
CY2012Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	916000000	USD
CY2011Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	721000000	USD
CY2012Q4	us-gaap	Assets Assets	30486000000	USD
CY2011Q4	us-gaap	Assets Assets	29552000000	USD
CY2012Q4	aon	Fiduciary Liabilities FiduciaryLiabilities	12214000000	USD
CY2011Q4	aon	Fiduciary Liabilities FiduciaryLiabilities	10838000000	USD
CY2012Q4	us-gaap	Debt Current DebtCurrent	452000000	USD
CY2011Q4	us-gaap	Debt Current DebtCurrent	337000000	USD
CY2012Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	1853000000	USD
CY2011Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	1832000000	USD
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CY2011Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	753000000	USD
CY2012Q4	us-gaap	Liabilities Current LiabilitiesCurrent	15350000000	USD
CY2011Q4	us-gaap	Liabilities Current LiabilitiesCurrent	13760000000	USD
CY2012Q4	us-gaap	Common Stock Value CommonStockValue	3000000	USD
CY2011Q4	us-gaap	Common Stock Value CommonStockValue	386000000	USD
CY2012Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	3713000000	USD
CY2011Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	4155000000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	306000000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	301000000	USD
CY2012Q4	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesNoncurrent	2276000000	USD
CY2011Q4	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesNoncurrent	2192000000	USD
CY2012Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	1036000000	USD
CY2011Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	1024000000	USD
CY2012Q4	us-gaap	Liabilities Liabilities	22681000000	USD
CY2011Q4	us-gaap	Liabilities Liabilities	21432000000	USD
CY2012Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	4436000000	USD
CY2011Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	4021000000	USD
CY2012Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	5933000000	USD
CY2011Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	8594000000	USD
CY2011Q4	us-gaap	Treasury Stock Value TreasuryStockValue	2553000000	USD
CY2012Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-2610000000	USD
CY2011Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-2370000000	USD
CY2012Q4	us-gaap	Stockholders Equity StockholdersEquity	7762000000	USD
CY2011Q4	us-gaap	Stockholders Equity StockholdersEquity	8078000000	USD
CY2012Q4	us-gaap	Minority Interest MinorityInterest	43000000	USD
CY2011Q4	us-gaap	Minority Interest MinorityInterest	42000000	USD
CY2012Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7805000000	USD
CY2011Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	8120000000	USD
CY2012Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	30486000000	USD
CY2011Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	29552000000	USD
CY2012Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2011Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1.00
CY2012Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	750000000	shares
CY2011Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	386400000	shares
CY2011Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	750000000	shares
CY2012Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	0	shares
CY2012Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	310900000	shares
CY2011Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	61600000	shares
CY2010Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	8306000000	USD
CY2010	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	2474000000	USD
CY2010Q4	aon	Noncash Or Part Noncash Acquisition Common Stock Issued And Stock Options Assumed NoncashOrPartNoncashAcquisitionCommonStockIssuedAndStockOptionsAssumed	2474000000	USD
CY2010	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	135000000	USD
CY2010	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	250000000	USD
CY2010	aon	Stock Issued During Period Value Treasury Stock Reissued Share Based Compensation StockIssuedDuringPeriodValueTreasuryStockReissuedShareBasedCompensation	-49000000	USD
CY2010	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	221000000	USD
CY2010	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	175000000	USD
CY2010	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	15000000	USD
CY2012	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	4000000	USD
CY2010	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	20000000	USD
CY2011	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	112000000	USD
CY2011	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	828000000	USD
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CY2011	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	235000000	USD
CY2011	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	200000000	USD
CY2011	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	24000000	USD
CY2011	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	30000000	USD
CY2012	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	29000000	USD
CY2012	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	1125000000	USD
CY2012	aon	Stock Issued During Period Value Treasury Stock Reissued Share Based Compensation StockIssuedDuringPeriodValueTreasuryStockReissuedShareBasedCompensation	-13000000	USD
CY2012	us-gaap	Adjustments To Additional Paid In Capital Tax Effect From Share Based Compensation AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation	33000000	USD
CY2012	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	212000000	USD
CY2012	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	204000000	USD
CY2012	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	27000000	USD
CY2012	dei	Entity Registrant Name EntityRegistrantName	Aon plc
CY2012	dei	Entity Central Index Key EntityCentralIndexKey	0000315293
CY2012	dei	Document Type DocumentType	10-K
CY2012	dei	Document Period End Date DocumentPeriodEndDate	2012-12-31
CY2012	dei	Amendment Flag AmendmentFlag	false
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CY2012	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2012	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2012	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	-585000000	USD
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CY2012	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-4000000	USD
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CY2012	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1419000000	USD
CY2010	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	783000000	USD
CY2011	aon	Disposal Group Including Discontinued Operation Gain Loss From Disposal DisposalGroupIncludingDiscontinuedOperationGainLossFromDisposal	6000000	USD
CY2012	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2012
CY2012	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
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CY2010	aon	Increase Decrease In Fiduciary Receivables IncreaseDecreaseInFiduciaryReceivables	-816000000	USD
CY2012	us-gaap	Increase Decrease In Client Funds Held IncreaseDecreaseInClientFundsHeld	-239000000	USD
CY2010	us-gaap	Increase Decrease In Client Funds Held IncreaseDecreaseInClientFundsHeld	19000000	USD
CY2012	aon	Increase Decrease In Fiduciary Liabilities IncreaseDecreaseInFiduciaryLiabilities	1163000000	USD
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CY2011	us-gaap	Adjustment For Amortization AdjustmentForAmortization	362000000	USD
CY2011	us-gaap	Share Based Compensation ShareBasedCompensation	235000000	USD
CY2011	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	146000000	USD
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CY2012	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	19000000	USD
CY2010	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1823000000	USD
CY2012	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	9000000	USD
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CY2012	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-106000000	USD
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CY2012	us-gaap	Increase Decrease In Restructuring Reserve IncreaseDecreaseInRestructuringReserve	-46000000	USD
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CY2012	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	185000000	USD
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CY2010	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	192000000	USD
CY2012	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2012	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2011Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	4492000000	USD
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CY2012Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	4165000000	USD
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CY2012Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-1000000	USD
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CY2012	aon	Common Stock Price Per Share High End Of Range CommonStockPricePerShareHighEndOfRange	57.92
CY2011	aon	Common Stock Price Per Share High End Of Range CommonStockPricePerShareHighEndOfRange	54.58
CY2012	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	item
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CY2010	us-gaap	Investment Income Interest InvestmentIncomeInterest	15000000	USD
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CY2012Q1	us-gaap	Profit Loss ProfitLoss	249000000	USD
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CY2010	aon	Uk Defined Contribution Plan Cost Recognized UKDefinedContributionPlanCostRecognized	35000000	USD
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CY2012	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	156000000	USD
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CY2012	aon	Common Stock Price Per Share Low End Of Range CommonStockPricePerShareLowEndOfRange	45.04
CY2011	aon	Common Stock Price Per Share Low End Of Range CommonStockPricePerShareLowEndOfRange	39.68
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CY2011Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	324400000	shares
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CY2012Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	461000000	USD
CY2012Q4	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	307000000	USD
CY2012Q4	us-gaap	Profit Loss ProfitLoss	307000000	USD
CY2012Q4	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	2000000	USD
CY2012Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	305000000	USD
CY2012Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.72
CY2012Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.74
CY2011Q1	aon	Fiduciary Investment Income FiduciaryInvestmentIncome	11000000	USD
CY2012Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.74
CY2012Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.62
CY2011Q1	us-gaap	Revenues Revenues	2759000000	USD
CY2012Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.62
CY2012Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.95
CY2011Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.01
CY2011Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.85
CY2012Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	302000000	USD
CY2011Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	398000000	USD
CY2012Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.95
CY2012Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.71
CY2011Q1	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	253000000	USD
CY2012Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.71
CY2012Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.73
CY2011Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	2000000	USD
CY2012Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.73
CY2012Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.62
CY2011Q1	us-gaap	Profit Loss ProfitLoss	255000000	USD
CY2012Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.62
CY2012Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.93
CY2011Q1	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	9000000	USD
CY2012Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.93
CY2011Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	246000000	USD
CY2011Q2	aon	Commissions Fees And Other CommissionsFeesAndOther	2799000000	USD
CY2011Q2	aon	Fiduciary Investment Income FiduciaryInvestmentIncome	12000000	USD
CY2011Q2	us-gaap	Revenues Revenues	2811000000	USD
CY2011Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	440000000	USD
CY2011Q2	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	265000000	USD
CY2011Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	2000000	USD
CY2011Q2	us-gaap	Profit Loss ProfitLoss	267000000	USD
CY2011Q2	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	9000000	USD
CY2011Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	258000000	USD
CY2011Q3	aon	Commissions Fees And Other CommissionsFeesAndOther	2708000000	USD
CY2011Q3	aon	Fiduciary Investment Income FiduciaryInvestmentIncome	15000000	USD
CY2011Q3	us-gaap	Revenues Revenues	2723000000	USD
CY2011Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	328000000	USD
CY2011Q3	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	208000000	USD
CY2011Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.72
CY2011Q3	us-gaap	Profit Loss ProfitLoss	208000000	USD
CY2011Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	10000000	USD
CY2011Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	198000000	USD
CY2011Q4	aon	Commissions Fees And Other CommissionsFeesAndOther	2980000000	USD
CY2011Q4	aon	Fiduciary Investment Income FiduciaryInvestmentIncome	14000000	USD
CY2011Q4	us-gaap	Revenues Revenues	2994000000	USD
CY2011Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	430000000	USD
CY2011Q4	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	280000000	USD
CY2012Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.15
CY2011Q4	us-gaap	Profit Loss ProfitLoss	280000000	USD
CY2011Q4	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	3000000	USD
CY2011Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	277000000	USD
CY2011Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.72
CY2011Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.76
CY2012Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.16
CY2011Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.76
CY2011Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.59
CY2012Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.16
CY2011Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.59
CY2011Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.84
CY2011Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.75
CY2012Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.16
CY2011Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.75
CY2011Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.71
CY2011Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.15
CY2011Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.71
CY2011Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.59
CY2011Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.15
CY2011Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.59
CY2011Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.82
CY2011Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.01
CY2011Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.83
CY2011Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.15
CY2011Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.15
CY2012	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	62000000	USD
CY2011	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	77000000	USD
CY2010	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	75000000	USD
CY2012	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	150000000	USD
CY2012	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P2Y1M6D
CY2012	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	212000000	USD
CY2011	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	235000000	USD
CY2010	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	221000000	USD
CY2011Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	157000000	USD
CY2012Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	210000000	USD
CY2011Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	189000000	USD
CY2011	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	158000000	USD
CY2010	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	146000000	USD
CY2012Q4	aon	Closing Stock Price ClosingStockPrice	55.61
CY2012Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	131000000	USD
CY2012Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	124000000	USD
CY2012	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	67000000	USD
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	80000000	USD
CY2010	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	87000000	USD
CY2012	us-gaap	Employee Service Share Based Compensation Cash Received From Exercise Of Stock Options EmployeeServiceShareBasedCompensationCashReceivedFromExerciseOfStockOptions	105000000	USD
CY2011	us-gaap	Employee Service Share Based Compensation Cash Received From Exercise Of Stock Options EmployeeServiceShareBasedCompensationCashReceivedFromExerciseOfStockOptions	153000000	USD
CY2010	us-gaap	Employee Service Share Based Compensation Cash Received From Exercise Of Stock Options EmployeeServiceShareBasedCompensationCashReceivedFromExerciseOfStockOptions	162000000	USD
CY2012	us-gaap	Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOptions	11000000	USD
CY2011	us-gaap	Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOptions	14000000	USD
CY2010	us-gaap	Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOptions	4000000	USD
CY2012Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	251000000	USD
CY2011Q4	invest	Derivative Notional Amount DerivativeNotionalAmount	2245000000	USD
CY2012Q4	invest	Derivative Notional Amount DerivativeNotionalAmount	2460000000	USD
CY2012Q4	aon	Hedge Gain Loss To Be Reclassified During Next12 Months HedgeGainLossToBeReclassifiedDuringNext12Months	20000000	USD
CY2012	aon	Payment On Dismissal Of Class Claims PaymentOnDismissalOfClassClaims	550000	USD
CY2012Q4	us-gaap	Loss Contingency Range Of Possible Loss Maximum LossContingencyRangeOfPossibleLossMaximum	104000000	USD
CY2012Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	74000000	USD
CY2011Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	75000000	USD
CY2012	aon	Fair Value Investments Fund Net Assets Fair Value FairValueInvestmentsFundNetAssetsFairValue	1
CY2012Q4	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	4162000000	USD
CY2011Q4	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	4494000000	USD
CY2010	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-18000000	USD
CY2012Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	2800000000	USD
CY2012	aon	Foreign Currency Transaction Gain Loss Before Tax Including Hedging ForeignCurrencyTransactionGainLossBeforeTaxIncludingHedging	-16000000	USD
CY2011	aon	Foreign Currency Transaction Gain Loss Before Tax Including Hedging ForeignCurrencyTransactionGainLossBeforeTaxIncludingHedging	10000000	USD
CY2012Q4	aon	Distributable Reserves Available Amount DistributableReservesAvailableAmount	7000000000	USD
CY2010	us-gaap	Other Comprehensive Income Cumulative Effect Of Change In Accounting Principle Net Of Taxes OtherComprehensiveIncomeCumulativeEffectOfChangeInAccountingPrincipleNetOfTaxes	-44000000	USD
CY2010	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.125	pure
CY2010	aon	Number Of Dispositions NumberOfDispositions	8	item
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.056	pure
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.017	pure
CY2010	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.002	pure
CY2012Q1	aon	Common Stock Average Shares Monthly Trading Volume CommonStockAverageSharesMonthlyTradingVolume	47000000	shares
CY2012Q2	aon	Common Stock Average Shares Monthly Trading Volume CommonStockAverageSharesMonthlyTradingVolume	47600000	shares
CY2012Q3	aon	Common Stock Average Shares Monthly Trading Volume CommonStockAverageSharesMonthlyTradingVolume	30100000	shares
CY2012Q4	aon	Common Stock Average Shares Monthly Trading Volume CommonStockAverageSharesMonthlyTradingVolume	33700000	shares
CY2012	aon	Common Stock Average Shares Monthly Trading Volume CommonStockAverageSharesMonthlyTradingVolume	39600000	shares
CY2011Q1	aon	Common Stock Average Shares Monthly Trading Volume CommonStockAverageSharesMonthlyTradingVolume	50700000	shares
CY2011Q2	aon	Common Stock Average Shares Monthly Trading Volume CommonStockAverageSharesMonthlyTradingVolume	40200000	shares
CY2011Q3	aon	Common Stock Average Shares Monthly Trading Volume CommonStockAverageSharesMonthlyTradingVolume	55300000	shares
CY2011Q4	aon	Common Stock Average Shares Monthly Trading Volume CommonStockAverageSharesMonthlyTradingVolume	56300000	shares
CY2011	aon	Common Stock Average Shares Monthly Trading Volume CommonStockAverageSharesMonthlyTradingVolume	50600000	shares
CY2011	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	24000000	USD
CY2010	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	15000000	USD
CY2012	aon	Income Tax Holiday Income Tax Benefits IncomeTaxHolidayIncomeTaxBenefits	11000000	USD
CY2010	aon	Foreign Currency Transaction Gain Loss Before Tax Including Hedging ForeignCurrencyTransactionGainLossBeforeTaxIncludingHedging	-18000000	USD
CY2011	aon	Restructuring Charges Noncash RestructuringChargesNoncash	106000000	USD
CY2010	aon	Restructuring Charges Noncash RestructuringChargesNoncash	168000000	USD
CY2012	aon	Restructuring Charges Noncash RestructuringChargesNoncash	97000000	USD
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.006	pure
CY2012	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	6000000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	6000000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	23000000	USD
CY2011Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	19000000	USD
CY2010	aon	Other Comprehensive Income Loss Excluding Cumulative Effect Of Change In Accounting Principle Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossExcludingCumulativeEffectOfChangeInAccountingPrincipleNetOfTaxPortionAttributableToParent	-198000000	USD

Files In Submission

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2012 Q4 Form 10-K Financial Statement

#000104746913001494 Filed on February 22, 2013

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AON Aon plc Stock $aon

2012 Q4 Form 10-K Financial Statement

#000104746913001494 Filed on February 22, 2013

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

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