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Fair Value of Financial Instruments - Carrying Values and Estimated Fair Values of Financial Instruments (Parenthetical) (Details) | Dec. 31, 2018 | Dec. 31, 2017
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Level 3 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Percentage of coinsurance costs | 10.00% | 10.00%

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- Definition Percentage of coinsurance covered costs. + 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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- Details
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