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Commitments, Contingencies and Off-Balance Sheet Arrangements - Litigation, Regulatory and Taxation Matters- Additional Information (Detail) $ in Millions | 12 Months Ended | 24 Months Ended
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Dec. 31, 2018 Companies | Dec. 31, 2018 USD ($)
Minimum [Member] |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |
Number of micro-captive insurance companies organized or managed | Companies | 100 |
Maximum [Member] |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |
Micro-captive operations, net earnings |  | $ 3.2
Micro-captive operations, EBITDAC |  | $ 5.0

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- Definition Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] + References No definition available. + Details
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- Definition Micro-captive operations, EBITDAC. + References No definition available. + Details
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- Details
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