v3.3.1.900

Fair Value Measurements - Fair Value Hierarchy (Details) | Dec. 31, 2015 USD ($) security | Dec. 31, 2014 USD ($) security
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, number of securities | security | 2 | 1
Other investments | $ 11,812,000 | $ 12,571,000
Investments in limited partnerships |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other investments | $ 5,907,000 | 5,581,000
Other investments, percent of assets | 0.10% |
Significant Other Observable Inputs (Level 2) | Available-for-sale fixed maturities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets valued using market approach, amount | $ 4,943,000 | 5,016,000
Fair Value, Measurements, Recurring | Total Fair Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other investments, fair value | 11,812,000 | 12,571,000
Total assets fair value | $ 3,519,900,000 | $ 3,469,475,000
Percentage of total assets | 61.60% | 67.20%
Fair Value, Measurements, Recurring | Total Fair Value | Available-for-sale fixed maturities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets valued by third party, percentage | 99.90% | 99.90%
Assets valued using market approach, percentage (in securities) | 0.10% | 0.10%
Fair Value, Measurements, Recurring | Total Fair Value | U.S. treasury bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | $ 6,010,000 | $ 9,360,000
Fair Value, Measurements, Recurring | Total Fair Value | U.S. agency bonds – mortgage-backed |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 1,476,991,000 | 1,322,443,000
Fair Value, Measurements, Recurring | Total Fair Value | U.S. agency bonds – other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 24,311,000 | 7,988,000
Fair Value, Measurements, Recurring | Total Fair Value | Non-U.S. government and supranational bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 30,544,000 | 51,643,000
Fair Value, Measurements, Recurring | Total Fair Value | Asset-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 165,804,000 | 54,780,000
Fair Value, Measurements, Recurring | Total Fair Value | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 1,739,668,000 | 1,895,379,000
Fair Value, Measurements, Recurring | Total Fair Value | Municipal bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 64,760,000 | 65,819,000
Fair Value, Measurements, Recurring | Total Fair Value | Short-term investments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value |  | 49,492,000
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other investments, fair value | 4,905,000 | 5,990,000
Total assets fair value | $ 10,915,000 | $ 15,350,000
Percentage of total assets | 0.20% | 0.30%
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. treasury bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | $ 6,010,000 | $ 9,360,000
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. agency bonds – mortgage-backed |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. agency bonds – other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Non-U.S. government and supranational bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Asset-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipal bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value |  | 0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other investments, fair value | 0 | 0
Total assets fair value | $ 3,502,078,000 | $ 3,447,544,000
Percentage of total assets | 61.30% | 66.80%
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. treasury bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | $ 0 | $ 0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. agency bonds – mortgage-backed |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 1,476,991,000 | 1,322,443,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. agency bonds – other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 24,311,000 | 7,988,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Non-U.S. government and supranational bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 30,544,000 | 51,643,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Asset-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 165,804,000 | 54,780,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 1,739,668,000 | 1,895,379,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Municipal bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 64,760,000 | 65,819,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Short-term investments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value |  | 49,492,000
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other investments, fair value | 6,907,000 | 6,581,000
Total assets fair value | $ 6,907,000 | $ 6,581,000
Percentage of total assets | 0.10% | 0.10%
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | U.S. treasury bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | $ 0 | $ 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | U.S. agency bonds – mortgage-backed |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | U.S. agency bonds – other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Non-U.S. government and supranational bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Asset-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Municipal bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Short-term investments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
AFS fixed maturities, fair value |  | $ 0
Preferred stock | Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other investments | $ 1,000,000 |

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