Fair Value Measurement- Assets Measured at Fair Value on Nonrecurring Basis (Detail) (USD $) In Millions, unless otherwise specified
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3 Months Ended |
Mar. 31, 2015
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Dec. 31, 2014
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Loans |
$ 73us-gaap_LoansReceivableFairValueDisclosure |
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$ 53us-gaap_LoansReceivableFairValueDisclosure |
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Change in fair value of loans of underlying collateral |
1bk_ChangeInFairValueOfLoansMeasuredOnNonrecurringBasisBasedOnFairValueOfUnderlyingCollateral |
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(3)bk_ChangeInFairValueOfLoansMeasuredOnNonrecurringBasisBasedOnFairValueOfUnderlyingCollateral |
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Fair Value, Measurements, Nonrecurring |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Loans |
110us-gaap_LoansReceivableFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
[1] |
114us-gaap_LoansReceivableFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
[1] |
Other assets |
7us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
[2] |
6us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
[2] |
Subtotal assets of consolidated investment management funds, at fair value |
117us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
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120us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
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Level 2 | Fair Value, Measurements, Nonrecurring |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Loans |
108us-gaap_LoansReceivableFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
[1] |
112us-gaap_LoansReceivableFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
[1] |
Other assets |
7us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
[2] |
6us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
[2] |
Subtotal assets of consolidated investment management funds, at fair value |
115us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
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118us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
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Level 3 | Fair Value, Measurements, Nonrecurring |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Loans |
2us-gaap_LoansReceivableFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
[1] |
2us-gaap_LoansReceivableFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
[1] |
Subtotal assets of consolidated investment management funds, at fair value |
$ 2us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
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$ 2us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember |
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