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Business Developments And Risks And Uncertainties (Narrative) (Detail) $ / shares in Units, $ in Millions | 6 Months Ended
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Jun. 30, 2018 USD ($) segments $ / shares shares
Business Acquisition [Line Items] |
Number of operating segments | segments | 3
Warrants outstanding | shares | 11,850,000
Warrant exercise price | $ / shares | $ 9.59
Treasury shares issued (in shares) | shares | 1,300,000
Zohar [Member] |
Business Acquisition [Line Items] |
Aggregate claim amount | $ | $ 919
Puerto Rico [Member] |
Business Acquisition [Line Items] |
Claims payments | $ | $ 276

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