v3.3.1.900

Investments - Schedule of Investments Reconciliation (Details) - USD ($) $ in Thousands | 3 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2015 | Dec. 31, 2015 | Dec. 31, 2014
Schedule of Investments [Line Items] |  |  |
Fair value of securities transferred from AFS to HTM | $ 608,722 |  |
AFS Transferred to HTM securities, unrealized gain | $ 244 |  |
Available-for-sale fixed maturities, Original or amortized cost |  | $ 3,562,864 | $ 3,379,864
Available-for-sale fixed maturities, Gross unrealized gains |  | 58,115 | 116,051
Available-for-sale fixed maturities, Gross unrealized losses |  | (112,891) | (39,011)
Fair value |  | 3,508,088 | 3,456,904
Fixed maturities, held-to-maturity, at amortized cost (fair value 2015: $598,975; 2014: $0) |  | 607,843 | 0
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain |  | 3,458 |
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss |  | (12,326) |
HTM securities, Fair Value |  | 598,975 | 0
Other Investments, Original or amortized cost |  | 10,816 | 10,862
Other investments, Gross unrealized gains |  | 1,091 | 1,709
Other investments, Gross unrealized losses |  | (95) | 0
Other investments |  | 11,812 | 12,571
Total investments, Original or amortized cost |  | 4,181,523 | 3,390,726
Investments, Gross unrealized gains |  | 62,664 | 117,760
Investments, Gross unrealized losses |  | (125,312) | (39,011)
Total investments, Fair value |  | 4,118,875 | 3,469,475
U.S. treasury bonds |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale fixed maturities, Original or amortized cost |  | 5,714 | 8,937
Available-for-sale fixed maturities, Gross unrealized gains |  | 312 | 423
Available-for-sale fixed maturities, Gross unrealized losses |  | (16) | 0
Fair value |  | 6,010 | 9,360
U.S. agency bonds – mortgage-backed |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale fixed maturities, Original or amortized cost |  | 1,471,782 | 1,313,834
Available-for-sale fixed maturities, Gross unrealized gains |  | 15,399 | 19,197
Available-for-sale fixed maturities, Gross unrealized losses |  | (10,190) | (10,588)
Fair value |  | 1,476,991 | 1,322,443
U.S. agency bonds – other |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale fixed maturities, Original or amortized cost |  | 23,734 | 7,213
Available-for-sale fixed maturities, Gross unrealized gains |  | 577 | 775
Available-for-sale fixed maturities, Gross unrealized losses |  | 0 | 0
Fair value |  | 24,311 | 7,988
Non-U.S. government and supranational bonds |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale fixed maturities, Original or amortized cost |  | 35,128 | 54,467
Available-for-sale fixed maturities, Gross unrealized gains |  | 0 | 304
Available-for-sale fixed maturities, Gross unrealized losses |  | (4,584) | (3,128)
Fair value |  | 30,544 | 51,643
Asset-backed securities |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale fixed maturities, Original or amortized cost |  | 165,719 | 52,337
Available-for-sale fixed maturities, Gross unrealized gains |  | 1,174 | 2,443
Available-for-sale fixed maturities, Gross unrealized losses |  | (1,089) | 0
Fair value |  | 165,804 | 54,780
Corporate bonds |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale fixed maturities, Original or amortized cost |  | 1,798,610 | 1,831,431
Available-for-sale fixed maturities, Gross unrealized gains |  | 38,070 | 89,243
Available-for-sale fixed maturities, Gross unrealized losses |  | (97,012) | (25,295)
Fair value |  | 1,739,668 | 1,895,379
Fixed maturities, held-to-maturity, at amortized cost (fair value 2015: $598,975; 2014: $0) |  | 607,843 |
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain |  | 3,458 |
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss |  | (12,326) |
HTM securities, Fair Value |  | 598,975 |
Municipal bonds |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale fixed maturities, Original or amortized cost |  | 62,177 | 62,153
Available-for-sale fixed maturities, Gross unrealized gains |  | 2,583 | 3,666
Available-for-sale fixed maturities, Gross unrealized losses |  | 0 | 0
Fair value |  | $ 64,760 | 65,819
Short-term investments |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale fixed maturities, Original or amortized cost |  |  | 49,492
Available-for-sale fixed maturities, Gross unrealized gains |  |  | 0
Available-for-sale fixed maturities, Gross unrealized losses |  |  | 0
Fair value |  |  | $ 49,492

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