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v3.8.0.1

Segment Reporting - Summary of Gross and Net Written and Earned Premiums, Underwriting Results, Ratios and Reserves for Each of Company's Business Segments (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross written premiums |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,360.9 | $ 3,147.0 | $ 2,997.3 |
Net written premiums |  |  |  |  |  |  |  |  |  |  |  |  | 2,212.5 | 2,593.7 | 2,646.2 |
Gross earned premiums |  |  |  |  |  |  |  |  |  |  |  |  | 3,209.2 | 3,086.3 | 2,856.8 |
Net earned premium | $ 511.0 | $ 652.5 | $ 562.0 | $ 581.1 | $ 612.4 | $ 681.0 | $ 680.8 | $ 663.1 | $ 629.7 | $ 640.6 | $ 609.4 | $ 593.6 | 2,306.6 | 2,637.3 | 2,473.3 |
Losses and loss adjustment expenses | 544.2 | 776.2 | 346.1 | 328.2 | 387.3 | 389.2 | 442.2 | 357.4 | 334.0 | 365.6 | 360.5 | 306.1 | 1,994.7 | 1,576.1 | 1,366.2 |
Amortization of deferred policy acquisition costs | 85.1 | 105.4 | 96.3 | 113.7 | 141.1 | 130.9 | 126.7 | 130.2 | 118.2 | 132.0 | 114.1 | 119.3 | 400.5 | 528.9 | 483.6 |
General and administrative expenses |  |  |  |  |  |  |  |  |  |  |  |  | 411.2 | 406.6 | 360.1 |
Underwriting income (loss) |  |  |  |  |  |  |  |  |  |  |  |  | (499.8) | 125.7 | 263.4 |
Corporate expenses |  |  |  |  |  |  |  |  |  |  |  |  | (58.3) | (73.8) | (63.9) |
Non-operating expenses |  |  |  |  |  |  |  |  |  |  |  |  | (32.7) | (9.7) |  |
Net investment income | 47.5 | 46.4 | 47.4 | 47.7 | 43.2 | 46.4 | 48.0 | 49.5 | 46.4 | 45.0 | 46.7 | 47.4 | 189.0 | 187.1 | 185.5 |
Realized and unrealized investment gains | 18.8 | 29.9 | 49.0 | 51.2 | (29.0) | 26.7 | 45.1 | 65.6 | 12.9 | 10.7 | 13.5 | 57.4 | 148.9 | 108.4 | 94.5 |
Realized and unrealized investment losses | (4.0) | (12.4) | (7.0) | (5.0) | (29.1) | (5.2) | (8.3) | (20.6) | 17.7 | (51.9) | (28.8) | (14.5) | (28.4) | (63.2) | (77.5) |
Change in fair value of loan notes issued by variable interest entities | 17.6 | 9.8 | (3.3) | (2.9) | (3.4) | (9.8) | 0.5 | (4.4) | (5.3) | (8.3) | (3.3) | (2.9) | 21.2 | (17.1) | (19.8) |
Change in fair value of derivatives | 2.5 | 4.5 | 17.6 | 3.1 | (17.6) | 0.6 | (0.4) | (7.2) | 2.5 | 10.1 | 2.0 | (7.8) | 27.7 | (24.6) | 6.8 |
Interest expense on long term debt | (7.3) | (7.4) | (7.4) | (7.4) | (7.4) | (7.3) | (7.4) | (7.4) | (7.4) | (7.4) | (7.3) | (7.4) | (29.5) | (29.5) | (29.5) |
Net realized and unrealized foreign exchange (losses) | (2.8) | 8.4 | (20.6) | (8.9) | 12.0 | 10.8 | (5.3) | (15.7) | 5.0 | (8.4) | (11.6) | (6.4) | (23.9) | 1.8 | (21.4) |
Other income | 3.9 | (2.2) | 3.6 | 3.6 | 3.3 | 1.5 | (0.5) | 1.4 | (0.3) | (2.3) | (1.2) | 3.9 | 8.9 | 5.7 | 0.1 |
Other expenses |  |  |  |  |  |  |  |  |  |  |  |  | (4.9) | (1.3) | (0.7) |
(Loss)/income from operations before income tax | (195.1) | (263.0) | 77.0 | 99.3 | (74.1) | 100.5 | 66.2 | 116.9 | 123.2 | 30.0 | 51.2 | 133.1 | (281.8) | 209.5 | 337.5 |
Income tax credit/(expense) | 10.2 | 9.2 | (1.2) | (2.8) | 2.6 | (4.9) | (1.3) | (2.5) | (5.3) | (1.8) | (2.2) | (5.1) | 15.4 | (6.1) | (14.4) |
Net (loss)/income | (184.9) | $ (253.8) | $ 75.8 | $ 96.5 | (71.5) | $ 95.6 | $ 64.9 | $ 114.4 | 117.9 | $ 28.2 | $ 49.0 | $ 128.0 | (266.4) | 203.4 | 323.1 |
Losses and loss adjustment expenses | 6,749.5 |  |  |  | 5,319.9 |  |  |  | 4,938.2 |  |  |  | 6,749.5 | 5,319.9 | 4,938.2 | $ 4,750.8
Net Reserves for Losses and LAE | 5,234.3 |  |  |  | 4,759.2 |  |  |  | 4,583.4 |  |  |  | $ 5,234.3 | $ 4,759.2 | $ 4,583.4 | $ 4,400.8
Ratios |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss ratio |  |  |  |  |  |  |  |  |  |  |  |  | 86.50% | 59.80% | 55.20% |
Policy acquisition expense ratio |  |  |  |  |  |  |  |  |  |  |  |  | 17.40% | 20.10% | 19.60% |
General and administrative expense ratio |  |  |  |  |  |  |  |  |  |  |  |  | 21.80% | 18.60% | 17.10% |
Expense ratio |  |  |  |  |  |  |  |  |  |  |  |  | 39.20% | 38.70% | 36.70% |
Combined ratio |  |  |  |  |  |  |  |  |  |  |  |  | 125.70% | 98.50% | 91.90% |
Reinsurance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net written premiums |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,250.0 | $ 1,269.2 | $ 1,153.5 |
Net earned premium |  |  |  |  |  |  |  |  |  |  |  |  | 1,206.1 | 1,181.9 | 1,072.6 |
Losses and loss adjustment expenses | 2,917.1 |  |  |  | 2,462.1 |  |  |  | 2,409.5 |  |  |  | 2,917.1 | 2,462.1 | 2,409.5 |
Net Reserves for Losses and LAE | 2,917.1 |  |  |  | 2,462.1 |  |  |  | 2,409.5 |  |  |  | $ 2,917.1 | $ 2,462.1 | $ 2,409.5 |
Ratios |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss ratio |  |  |  |  |  |  |  |  |  |  |  |  | 92.60% | 55.70% | 45.80% |
Policy acquisition expense ratio |  |  |  |  |  |  |  |  |  |  |  |  | 19.50% | 19.20% | 20.90% |
General and administrative expense ratio |  |  |  |  |  |  |  |  |  |  |  |  | 13.00% | 15.10% | 13.70% |
Expense ratio |  |  |  |  |  |  |  |  |  |  |  |  | 32.50% | 34.30% | 34.60% |
Combined ratio |  |  |  |  |  |  |  |  |  |  |  |  | 125.10% | 90.00% | 80.40% |
Insurance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net written premiums |  |  |  |  |  |  |  |  |  |  |  |  | $ 962.5 | $ 1,324.5 | $ 1,492.7 |
Net earned premium |  |  |  |  |  |  |  |  |  |  |  |  | 1,100.5 | 1,455.4 | 1,400.7 |
Losses and loss adjustment expenses | 2,317.2 |  |  |  | 2,297.1 |  |  |  | 2,173.9 |  |  |  | 2,317.2 | 2,297.1 | 2,173.9 |
Net Reserves for Losses and LAE | $ 2,317.2 |  |  |  | $ 2,297.1 |  |  |  | $ 2,173.9 |  |  |  | $ 2,317.2 | $ 2,297.1 | $ 2,173.9 |
Ratios |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss ratio |  |  |  |  |  |  |  |  |  |  |  |  | 79.80% | 63.10% | 62.40% |
Policy acquisition expense ratio |  |  |  |  |  |  |  |  |  |  |  |  | 15.00% | 20.80% | 18.50% |
General and administrative expense ratio |  |  |  |  |  |  |  |  |  |  |  |  | 23.10% | 15.70% | 15.20% |
Expense ratio |  |  |  |  |  |  |  |  |  |  |  |  | 38.10% | 36.50% | 33.70% |
Combined ratio |  |  |  |  |  |  |  |  |  |  |  |  | 117.90% | 99.60% | 96.10% |
Operating Segments | Reinsurance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross written premiums |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,548.5 | $ 1,413.2 | $ 1,248.9 |
Net written premiums |  |  |  |  |  |  |  |  |  |  |  |  | 1,250.0 | 1,269.2 | 1,153.5 |
Gross earned premiums |  |  |  |  |  |  |  |  |  |  |  |  | 1,451.8 | 1,317.9 | 1,153.5 |
Net earned premium |  |  |  |  |  |  |  |  |  |  |  |  | 1,206.1 | 1,181.9 | 1,072.6 |
Losses and loss adjustment expenses |  |  |  |  |  |  |  |  |  |  |  |  | 1,116.4 | 657.9 | 491.6 |
Amortization of deferred policy acquisition costs |  |  |  |  |  |  |  |  |  |  |  |  | 235.5 | 226.4 | 224.7 |
General and administrative expenses |  |  |  |  |  |  |  |  |  |  |  |  | 157.3 | 178.2 | 146.5 |
Underwriting income (loss) |  |  |  |  |  |  |  |  |  |  |  |  | (303.1) | 119.4 | 209.8 |
Operating Segments | Insurance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross written premiums |  |  |  |  |  |  |  |  |  |  |  |  | 1,812.4 | 1,733.8 | 1,748.4 |
Net written premiums |  |  |  |  |  |  |  |  |  |  |  |  | 962.5 | 1,324.5 | 1,492.7 |
Gross earned premiums |  |  |  |  |  |  |  |  |  |  |  |  | 1,757.4 | 1,768.4 | 1,703.3 |
Net earned premium |  |  |  |  |  |  |  |  |  |  |  |  | 1,100.5 | 1,455.4 | 1,400.7 |
Losses and loss adjustment expenses |  |  |  |  |  |  |  |  |  |  |  |  | 878.3 | 918.2 | 874.6 |
Amortization of deferred policy acquisition costs |  |  |  |  |  |  |  |  |  |  |  |  | 165.0 | 302.5 | 258.9 |
General and administrative expenses |  |  |  |  |  |  |  |  |  |  |  |  | 253.9 | 228.4 | 213.6 |
Underwriting income (loss) |  |  |  |  |  |  |  |  |  |  |  |  | $ (196.7) | $ 6.3 | $ 53.6 |

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- Definition Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.5) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6811-158387 + Details
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