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Fair Value Measurements (Summary Of Quantitative Information About Level 3 Fair Value Measurements) (Details) | 9 Months Ended
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Sep. 30, 2022 Rate
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
Valuation Technique, Discounted cash flow | Discounted cash flow |
Auction rate securities |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
Valuation Technique, Discounted cash flow | Discounted cash flow |
Estimated market recovery period | 5 years |
Auction rate securities | Minimum [Member] |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
Estimated market rate | 5.80% |
Auction rate securities | Maximum [Member] |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
Estimated market rate | 6.50% |
Auction rate securities | Weighted Average [Member] |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
Estimated market recovery period | 5 years | [1]
Estimated market rate | 6.10% | [1]
Private Equity Investments |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
Valuation Technique, Market comparable companies | Market comparable companies |
Private Equity Investments | Minimum [Member] |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
EBITDA multiple | 4.0 |
Private Equity Investments | Maximum [Member] |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
EBITDA multiple | 7.0 |
Private Equity Investments | Weighted Average [Member] |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
EBITDA multiple | 5.5 | [1]
Mortgage loan commitments |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
Valuation Technique, Discounted cash flow | Discounted cash flow |
Mortgage loan commitments | Minimum [Member] |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
Probability of funding | 87.70% |
Embedded servicing value | 1.00% |
Mortgage loan commitments | Maximum [Member] |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
Probability of funding | 100.00% |
Embedded servicing value | 1.50% |
Mortgage loan commitments | Weighted Average [Member] |  |
Fair Value Assets Measured on Recurring Basis [Line Items] |  |
Probability of funding | 91.10% | [1]
Embedded servicing value | 1.30% | [1]
[1] | * Unobservable inputs were weighted by the relative fair value of the instruments.

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- Definition Fair value, discounted cash flow, valuation techniques. + References No definition available. + Details
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- Definition Fair value, estimated market rate, percent. + References No definition available. + Details
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- Definition Fair Value, Earnings before interest, taxes, depreciation, amortization (EBITDA) multiple. + 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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