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Fair Value Measurements - Information about Valuation Inputs for Fixed Income Securities Classified as Level 3 (Detail) - Successor [Member] | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2015 | Dec. 31, 2014
Corporate Obligations [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Coupon rate | 0.345% |
Fair Value Inputs Maturity | 19 years 1 month 21 days |
Yield | 4.93% |
Variable Interest Entity, Primary Beneficiary [Member] | United States Transactions [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Coupon rate | 5.88% | 5.88%
Fair Value Inputs Maturity | 22 years 23 days | 16 years 4 months 18 days
Yield | 9.00% | 7.77%
Variable Interest Entity, Primary Beneficiary [Member] | European Transactions [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Coupon rate | 0.54% | 0.30%
Fair Value Inputs Maturity | 17 years 5 months 5 days | 21 years 2 months 30 days
Yield | 7.46% | 9.52%

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- Definition Fair value inputs coupon rate. + References No definition available. + Details
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- Definition Fair value inputs maturity. + References No definition available. + Details
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- Definition Fair value inputs yield. + References No definition available. + Details
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