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Consolidated Statements of Shareholders' Equity (USD $) In Millions, unless otherwise specified | Total | Ordinary Shares and Additional Paid-in Capital [Member] | Retained Earnings [Member] | Treasury Stock [Member] | Accumulated Other Comprehensive Loss, Net of Tax [Member] | Noncontrolling Interests [Member]
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Balance at Dec. 31, 2011 | $ 8,120 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | $ 4,407 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember | $ 8,594 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | $ (2,553)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember | $ (2,370)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember | $ 42 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Balance (in shares) at Dec. 31, 2011 |  | 386.4 us-gaap_CommonStockSharesIssued / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Increase (Decrease) in Shareholders' Equity |  |  |  |  |  |
Net income | 1,020 us-gaap_ProfitLoss |  | 993 us-gaap_ProfitLoss / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  | 27 us-gaap_ProfitLoss / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Retirement of treasury shares (in shares) |  | (60.0)us-gaap_TreasuryStockSharesRetired / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Retirement of treasury shares | 0 us-gaap_TreasuryStockRetiredCostMethodAmount | (60)us-gaap_TreasuryStockRetiredCostMethodAmount / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember | (2,412)us-gaap_TreasuryStockRetiredCostMethodAmount / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | 2,472 us-gaap_TreasuryStockRetiredCostMethodAmount / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember |  |
Shares issued - employee benefit plans (in shares) |  | 4.0 us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Shares issued — employee benefit plans | 29 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation | 29 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember | 0 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |
Shares purchased (in shares) |  | (19.5)us-gaap_TreasuryStockSharesAcquired / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Shares purchased | (1,125)us-gaap_TreasuryStockValueAcquiredCostMethod |  | (1,025)us-gaap_TreasuryStockValueAcquiredCostMethod / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | (100)us-gaap_TreasuryStockValueAcquiredCostMethod / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember |  |
Shares reissued — employee benefit plans | (13)aon_StockIssuedDuringPeriodValueTreasuryStockReissuedShareBasedCompensation | (181)aon_StockIssuedDuringPeriodValueTreasuryStockReissuedShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember | (13)aon_StockIssuedDuringPeriodValueTreasuryStockReissuedShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | 181 aon_StockIssuedDuringPeriodValueTreasuryStockReissuedShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember |  |
Tax benefit — employee benefit plans | 33 us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation | 33 us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Share-based compensation expense | 212 us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue | 212 us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Dividends to shareholders | (204)us-gaap_DividendsCommonStockCash |  | (204)us-gaap_DividendsCommonStockCash / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |
Change in fair value of investments | 0 us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax |  |  |  |  |
Net change in fair value of derivatives | 9 us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax |  |  |  | 9 us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |
Net foreign currency translation adjustments | 109 us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax |  |  |  | 109 us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |
Net post-retirement benefit obligation | (358)us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax |  |  |  | (358)us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |
Purchase of subsidiary shares from non-controlling interest | 0 us-gaap_MinorityInterestDecreaseFromRedemptions | (1)us-gaap_MinorityInterestDecreaseFromRedemptions / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  | 1 us-gaap_MinorityInterestDecreaseFromRedemptions / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Dividends paid to non-controlling interests on subsidiary common stock | (27)us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders |  |  |  |  | (27)us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Balance at Dec. 31, 2012 | 7,805 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | 4,439 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember | 5,933 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | 0 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember | (2,610)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember | 43 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Balance (in shares) at Dec. 31, 2012 |  | 310.9 us-gaap_CommonStockSharesIssued / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Increase (Decrease) in Shareholders' Equity |  |  |  |  |  |
Net income | 1,148 us-gaap_ProfitLoss |  | 1,113 us-gaap_ProfitLoss / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  | 35 us-gaap_ProfitLoss / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Shares issued - employee benefit plans (in shares) |  | 0.7 us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Shares issued — employee benefit plans | 27 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation | 28 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember | (1)us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |
Shares issued - employee compensation (in shares) |  | 5.9 us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Shares issued — employee compensation | (50)us-gaap_StockIssuedDuringPeriodValueEmployeeBenefitPlan | (50)us-gaap_StockIssuedDuringPeriodValueEmployeeBenefitPlan / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Shares purchased (in shares) |  | (16.8)us-gaap_TreasuryStockSharesAcquired / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Shares purchased | (1,102)us-gaap_TreasuryStockValueAcquiredCostMethod |  | (1,102)us-gaap_TreasuryStockValueAcquiredCostMethod / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |
Tax benefit — employee benefit plans | 74 us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation | 74 us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Share-based compensation expense | 300 us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue | 300 us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Dividends to shareholders | (212)us-gaap_DividendsCommonStockCash |  | (212)us-gaap_DividendsCommonStockCash / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |
Change in fair value of investments | 1 us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax |  |  |  | 1 us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |
Net change in fair value of derivatives | 6 us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax |  |  |  | 6 us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |
Net foreign currency translation adjustments | (65)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax |  |  |  | (64)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember | (1)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Net post-retirement benefit obligation | 293 us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax |  |  |  | 293 us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |
Purchase of subsidiary shares from non-controlling interest | (11)us-gaap_MinorityInterestDecreaseFromRedemptions | (3)us-gaap_MinorityInterestDecreaseFromRedemptions / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  | (8)us-gaap_MinorityInterestDecreaseFromRedemptions / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Dividends paid to non-controlling interests on subsidiary common stock | (19)us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders |  |  |  |  | (19)us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Balance at Dec. 31, 2013 | 8,195 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | 4,788 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember | 5,731 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | 0 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember | (2,374)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember | 50 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Balance (in shares) at Dec. 31, 2013 | 300.7 us-gaap_CommonStockSharesIssued | 300.7 us-gaap_CommonStockSharesIssued / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Increase (Decrease) in Shareholders' Equity |  |  |  |  |  |
Net income | 1,431 us-gaap_ProfitLoss |  | 1,397 us-gaap_ProfitLoss / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  | 34 us-gaap_ProfitLoss / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Shares issued - employee benefit plans (in shares) |  | 0.4 us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Shares issued — employee benefit plans | 26 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation | 26 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember | 0 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |
Shares issued - employee compensation (in shares) |  | 4.7 us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Shares issued — employee compensation | (131)us-gaap_StockIssuedDuringPeriodValueEmployeeBenefitPlan | (131)us-gaap_StockIssuedDuringPeriodValueEmployeeBenefitPlan / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Shares purchased (in shares) |  | (25.8)us-gaap_TreasuryStockSharesAcquired / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Shares purchased | (2,250)us-gaap_TreasuryStockValueAcquiredCostMethod |  | (2,250)us-gaap_TreasuryStockValueAcquiredCostMethod / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |
Tax benefit — employee benefit plans | 89 us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation | 89 us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Share-based compensation expense | 328 us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue | 328 us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |
Dividends to shareholders | (273)us-gaap_DividendsCommonStockCash |  | (273)us-gaap_DividendsCommonStockCash / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |
Change in fair value of investments | (1)us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax |  |  |  | (1)us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |
Net change in fair value of derivatives | 5 us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax |  |  |  | 5 us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |
Net foreign currency translation adjustments | (507)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax |  |  |  | (504)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember | (3)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Net post-retirement benefit obligation | (260)us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax |  |  |  | (260)us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |
Sales of subsidiary shares to non-controlling interest | 3 us-gaap_NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest |  |  |  |  | 3 us-gaap_NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Dividends paid to non-controlling interests on subsidiary common stock | (24)us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders |  |  |  |  | (24)us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Balance at Dec. 31, 2014 | $ 6,631 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | $ 5,100 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember | $ 4,605 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | $ 0 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember | $ (3,134)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember | $ 60 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember
Balance (in shares) at Dec. 31, 2014 | 280.0 us-gaap_CommonStockSharesIssued | 280.0 us-gaap_CommonStockSharesIssued / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember |  |  |  |

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- Definition Equity impact of the value of treasury stock (units) reissued during the period, used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding. + References No definition available. + Details
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- Definition This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation". + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415241&loc=d3e4534-113899 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 20 -Section 55 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=32706628&loc=d3e11149-113907 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=32706628&loc=d3e11178-113907 + Details
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- Definition Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 740 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6419406&loc=d3e23524-113945 + Details
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- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 + Details
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- Definition Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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