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Schedule I - Summay of Investments - Other Than Investments in Related Parties (Details) $ in Thousands | Dec. 31, 2016 USD ($)
--- | ---
Amortized Cost or Cost | $ 5,300,143
Carrying Amount | 5,364,947
Short-term Investments [Member] |
Amortized Cost or Cost | 221,701
Fair Value | 221,701
Carrying Amount | 221,701
Other Investments [Member] |
Amortized Cost or Cost | 102,397
Carrying Amount | 102,397
Preferred Stock [Member] | Banks, trusts, and insurance companies |
Amortized Cost or Cost | 16,226
Fair Value | 16,145
Carrying Amount | 16,145
Held-to-maturity Securities [Member] | Obligations of States and Political Subdivisions [Member] |
Amortized Cost or Cost | 77,466
Fair Value | 79,916
Carrying Amount | 77,783
Held-to-maturity Securities [Member] | Public Utilities |
Amortized Cost or Cost | 8,589
Fair Value | 9,292
Carrying Amount | 8,579
Held-to-maturity Securities [Member] | All other corporate securities |
Amortized Cost or Cost | 14,122
Fair Value | 14,783
Carrying Amount | 13,989
Held-to-maturity Securities [Member] | Commercial Mortgage-backed Securities (CMBS) [Member] |
Amortized Cost or Cost | 1,220
Fair Value | 1,220
Carrying Amount | 1,205
Held-to-maturity Securities [Member] | Fixed Income Securities [Member] |
Amortized Cost or Cost | 101,397
Fair Value | 105,211
Carrying Amount | 101,556
AFS Fixed Income Securities [Member] | US Government Agencies Debt Securities [Member] |
Amortized Cost or Cost | 75,139
Fair Value | 77,333
Carrying Amount | 77,333
AFS Fixed Income Securities [Member] | Foreign Government |
Amortized Cost or Cost | 26,559
Fair Value | 26,865
Carrying Amount | 26,865
AFS Fixed Income Securities [Member] | Obligations of States and Political Subdivisions [Member] |
Amortized Cost or Cost | 1,366,287
Fair Value | 1,379,593
Carrying Amount | 1,379,593
AFS Fixed Income Securities [Member] | Public Utilities |
Amortized Cost or Cost | 108,664
Fair Value | 110,000
Carrying Amount | 110,000
AFS Fixed Income Securities [Member] | All other corporate securities |
Amortized Cost or Cost | 1,867,892
Fair Value | 1,887,753
Carrying Amount | 1,887,753
AFS Fixed Income Securities [Member] | CLO and Other ABS |
Amortized Cost or Cost | 527,876
Fair Value | 528,960
Carrying Amount | 528,960
AFS Fixed Income Securities [Member] | Commercial Mortgage-backed Securities (CMBS) [Member] |
Amortized Cost or Cost | 256,356
Fair Value | 256,842
Carrying Amount | 256,842
AFS Fixed Income Securities [Member] | Fixed Income Securities [Member] |
Amortized Cost or Cost | 4,753,759
Fair Value | 4,792,540
Carrying Amount | 4,792,540
AFS Fixed Income Securities [Member] | Residential Mortgage Backed Securities [Member] |
Amortized Cost or Cost | 524,986
Fair Value | 525,194
Carrying Amount | 525,194
Equity Securities [Member] | Common Stock [Member] |
Amortized Cost or Cost | 104,663
Fair Value | 130,608
Carrying Amount | 130,608
Equity Securities [Member] | Preferred Stock [Member] |
Amortized Cost or Cost | 16,226
Fair Value | 16,145
Carrying Amount | 16,145
Equity Securities [Member] | Equity Securities [Member] |
Amortized Cost or Cost | 120,889
Fair Value | 146,753
Carrying Amount | 146,753
Common Stock [Member] | Banks, trusts, and insurance companies |
Amortized Cost or Cost | 14,056
Fair Value | 17,648
Carrying Amount | 17,648
Common Stock [Member] | Industrial, miscellaneous and all other |
Amortized Cost or Cost | 90,607
Fair Value | 112,960
Carrying Amount | $ 112,960

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- Definition This element represents the carrying (reported) amount of the entity's investments as of the balance sheet date. This amount may represent the individual investment's or group of similar investments' original cost, fair value, or such other amount at which the investment is shown in the entity's balance sheet. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 7 -Subparagraph (SX 210.12-15) -URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611379-123010 + Details
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