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Fair Value Of Financial Instruments (Narrative) (Detail) | Dec. 31, 2017 | Dec. 31, 2016
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Percentage of level 3 assets at fair value in total assets measured at fair value value | 30.00% | 21.00%
Percentage of level 3 liabilities at fair value in total liabilities measured at fair value | 41.00% | 37.00%

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- Definition Approximate percentage of level 3 liabilities at fair value in total liabilities measured at fair value. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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