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Fair Value Of Financial Instruments (Narrative) (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016 | Dec. 31, 2016
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 | 27.00% |  | 27.00% |  | 21.00%
Percentage of level 3 liabilities at fair value in total liabilities measured at fair value | 41.00% |  | 41.00% |  | 37.00%
Transfers into or out of Level 1 | $ 0 | $ 0 | $ 0 | $ 0 |

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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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