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Schedule I - Summary Of Investments (Details) - Successor [Member] - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 | Apr. 30, 2013
--- | --- | --- | ---
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Summary of Investments, Other than Investments in Related Parties, Cost | $ 5,567,562 |  |
Investments | 5,644,720 | $ 5,507,034 | $ 6,457,264
Available-for-sale Securities, Amortized Cost Basis | 5,283,157 | 4,939,325 |
Available-for-sale Securities | 5,334,120 | 5,150,018 |
Other Investments and Securities, at Cost | 284,405 |  |
Other investments | 310,600 | 357,016 |
U S Government Obligations [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities | 91,242 |  |
U.S. Government Obligations [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Summary of Investments, Other than Investments in Related Parties, Cost | 90,698 |  |
Residential Mortgage-Backed Securities [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 1,942,285 |  |
Available-for-sale Securities | 1,977,338 |  |
Collateralized Debt Obligations [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 85,706 |  |
Available-for-sale Securities | 84,267 |  |
Asset-backed Securities [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 802,842 |  |
Available-for-sale Securities | 840,527 |  |
Corporate Debt Securities [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities | 2,588,556 | 2,743,050 |
Short-term Investments [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 225,789 | 360,069 |
Available-for-sale Securities | 225,789 | 360,065 |
Fixed Income Securities [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 4,992,756 | 4,514,878 |
Available-for-sale Securities | 5,043,776 | 4,725,686 |
Fixed Income Securities [Member] | U.S. Agency Obligations [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 4,239 | 29,524 |
Available-for-sale Securities | 4,212 | 29,486 |
Fixed Income Securities [Member] | Municipal Bonds [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 424,048 | 523,019 |
Available-for-sale Securities | 420,770 | 525,792 |
Fixed Income Securities [Member] | Residential Mortgage-Backed Securities [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 1,942,285 | 1,557,059 |
Available-for-sale Securities | 1,977,338 | 1,710,955 |
Fixed Income Securities [Member] | Collateralized Debt Obligations [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 85,706 | 21,346 |
Available-for-sale Securities | 84,267 | 21,122 |
Fixed Income Securities [Member] | Asset-backed Securities [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 802,842 | 833,366 |
Available-for-sale Securities | 840,527 | 882,001 |
Fixed Income Securities [Member] | Corporate Debt Securities [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 1,610,912 | 1,382,195 |
Available-for-sale Securities | 1,593,669 | 1,385,594 |
Fixed Income Securities [Member] | Foreign Government Debt Securities [Member] |  |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost Basis | 96,638 | 126,041 |
Available-for-sale Securities | $ 96,306 | $ 127,757 |

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562 + Details
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- Definition Sum of the carrying amounts as of the balance sheet date of all investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(h)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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