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v3.3.1.900

Third Party Reinsurance (Written and Earned Premiums) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Written premiums: |  |  |
Direct | $ 1,325,700,000 | $ 1,296,300,000 | $ 1,116,700,000
Assumed | 36,000,000 | 65,900,000 | 59,800,000
Gross written premiums | 1,361,700,000 | 1,362,200,000 | 1,176,500,000
Ceded | (189,100,000) | (123,200,000) | (74,300,000)
Net written premiums | 1,172,600,000 | 1,239,000,000 | 1,102,200,000
Earned premiums: |  |  |
Gross amount | 1,322,000,000 | 1,233,500,000 | 1,043,800,000
Assumed from other companies | 45,900,000 | 70,900,000 | 148,500,000
Gross earned premiums | 1,367,900,000 | 1,304,400,000 | 1,192,300,000
Ceded | (179,700,000) | (119,400,000) | (71,400,000)
Net earned premiums | 1,188,200,000 | 1,185,000,000 | 1,120,900,000
Losses and LAE: |  |  |
Direct | 802,500,000 | 802,800,000 | 584,900,000
Policyholder Benefits and Claims Incurred, Assumed | 55,700,000 | 115,700,000 | 76,300,000
Gross losses and LAE | 858,200,000 | 918,500,000 | 661,200,000
Ceded | (149,300,000) | (94,500,000) | (39,100,000)
Total incurred losses and LAE | 708,900,000 | 824,000,000 | 622,100,000
OneBeacon |  |  |
Written premiums: |  |  |
Direct | 1,279,900,000 | 1,257,500,000 | 1,103,100,000
Assumed | 36,000,000 | 65,900,000 | 59,800,000
Gross written premiums | 1,315,900,000 | 1,323,400,000 | 1,162,900,000
Ceded | (179,300,000) | (106,500,000) | (74,300,000)
Net written premiums | 1,136,600,000 | 1,216,900,000 | 1,088,600,000
Earned premiums: |  |  |
Gross amount | 1,298,000,000 | 1,209,100,000 | 1,043,300,000
Assumed from other companies | 45,900,000 | 70,900,000 | 148,500,000
Gross earned premiums | 1,343,900,000 | 1,280,000,000 | 1,191,800,000
Ceded | (167,700,000) | (102,900,000) | (71,400,000)
Net earned premiums | 1,176,200,000 | 1,177,100,000 | 1,120,400,000
Losses and LAE: |  |  |
Direct | 783,000,000 | 778,700,000 | 584,900,000
Policyholder Benefits and Claims Incurred, Assumed | 55,700,000 | 115,700,000 | 76,300,000
Gross losses and LAE | 838,700,000 | 894,400,000 | 661,200,000
Ceded | (138,000,000) | (79,300,000) | (39,100,000)
Total incurred losses and LAE | 700,700,000 | 815,100,000 | 622,100,000
HG/BAM |  |  |
Written premiums: |  |  |
Direct | 25,900,000 | 16,200,000 | 13,600,000
Assumed | 0 | 0 | 0
Gross written premiums | 25,900,000 | 16,200,000 | 13,600,000
Ceded | 0 | 0 | 0
Net written premiums | 25,900,000 | 16,200,000 | 13,600,000
Earned premiums: |  |  |
Gross amount | 3,300,000 | 1,800,000 | 500,000
Assumed from other companies | 0 | 0 | 0
Gross earned premiums | 3,300,000 | 1,800,000 | 500,000
Ceded | 0 | 0 | 0
Net earned premiums | 3,300,000 | 1,800,000 | 500,000
Losses and LAE: |  |  |
Direct | 0 | 0 | 0
Policyholder Benefits and Claims Incurred, Assumed | 0 | 0 | 0
Gross losses and LAE | 0 | 0 | 0
Ceded | 0 | 0 | 0
Total incurred losses and LAE | 0 | 0 | 0
HG/BAM [Member] |  |  |
Written premiums: |  |  |
Ceded | (19,300,000) | (12,300,000) | (10,600,000)
Earned premiums: |  |  |
Ceded | (16,000,000) | (1,400,000) | (10,200,000.0)
Star & Shield Insurance Exchange [Member] |  |  |
Written premiums: |  |  |
Ceded |  | (16,000,000) |
Earned premiums: |  |  |
Ceded |  | (15,700,000) |
Other Segments |  |  |
Written premiums: |  |  |
Direct | 19,900,000 | 22,600,000 |
Assumed | 0 | 0 |
Gross written premiums | 19,900,000 | 22,600,000 |
Ceded | (9,800,000) | (16,700,000) |
Net written premiums | 10,100,000 | 5,900,000 |
Earned premiums: |  |  |
Gross amount | 20,700,000 | 22,600,000 |
Assumed from other companies | 0 | 0 |
Gross earned premiums | 20,700,000 | 22,600,000 |
Ceded | (12,000,000) | (16,500,000) |
Net earned premiums | 8,700,000 | 6,100,000 | 0
Losses and LAE: |  |  |
Direct | 19,500,000 | 24,100,000 |
Policyholder Benefits and Claims Incurred, Assumed | 0 | 0 |
Gross losses and LAE | 19,500,000 | 24,100,000 |
Ceded | (11,300,000) | (15,200,000) |
Total incurred losses and LAE | 8,200,000 | 8,900,000 | $ 0
AMTrust [Member] |  |  |
Written premiums: |  |  |
Ceded | (33,300,000) |  |
Earned premiums: |  |  |
Ceded | (33,300,000) |  |
Losses and LAE: |  |  |
Ceded | $ 33,400,000 |  |
Percentage of Quota Share Reinsurance Agreement | 100.00% |  |
Star & Shield Insurance Exchange [Member] |  |  |
Losses and LAE: |  |  |
Ceded |  | $ (16,900,000) |

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