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v3.10.0.1

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 | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017 | Dec. 31, 2016
Underwriting Revenues |  |  |  |  |  |
Gross written premiums | $ 853.8 | $ 822.1 | $ 1,970.6 | $ 1,820.1 |  |
Net written premiums | 486.0 | 578.7 | 1,121.5 | 1,264.9 |  |
Gross earned premiums | 845.5 | 749.7 | 1,688.1 | 1,501.0 |  |
Net earned premiums | 519.5 | 562.0 | 1,053.0 | 1,143.1 |  |
Underwriting Expenses |  |  |  |  |  |
Losses and loss adjustment expenses | 310.4 | 346.1 | 620.6 | 674.3 |  |
Amortization of deferred policy acquisition costs | 85.9 | 96.3 | 176.7 | 210.0 |  |
General and administrative expenses | 85.1 | 106.4 | 180.3 | 212.1 |  |
Underwriting income | 38.1 | 13.2 | 75.4 | 46.7 |  |
Corporate expenses | (16.0) | (11.4) | (29.7) | (24.8) |  |
Nonoperating Income (Expense) | (9.1) | (2.1) | (21.2) | (4.3) |  |
Net investment income | 50.4 | 47.4 | 97.7 | 95.1 |  |
Realized and unrealized investment gains | 3.5 | 49.0 | 104.1 | 100.2 |  |
Realized and unrealized investment losses | (24.2) | (7.0) | (162.5) | (12.0) |  |
Realized loss on the debt extinguishment | (8.6) | 0.0 | (8.6) | 0.0 |  |
Change in fair value of loan notes issued by variable interest entities | (3.4) | (3.3) | (2.4) | (6.2) |  |
Change in fair value of derivatives | (46.1) | 17.6 | (22.6) | 20.7 |  |
Interest expense on long term debt | (7.6) | (7.4) | (15.0) | (14.8) |  |
Net realized and unrealized foreign exchange gains | 5.2 | (20.6) | 0.5 | (29.5) |  |
Other income | 2.1 | 3.6 | 4.2 | 7.2 |  |
Other expenses | (0.5) | (2.0) | (1.7) | (2.0) |  |
(Loss)/income from operations before income tax | (16.2) | 77.0 | 18.2 | 176.3 |  |
Net reserves for loss and loss adjustment expenses | $ 4,876.4 | $ 4,792.0 | $ 4,876.4 | $ 4,792.0 | $ 5,234.3 | $ 4,759.2
Ratios |  |  |  |  |  |
Loss ratio | 59.70% | 61.60% | 58.90% | 59.00% |  |
Policy acquisition expense ratio | 16.50% | 17.10% | 16.80% | 18.40% |  |
General and administrative expense ratio | 21.20% | 21.30% | 22.00% | 21.10% |  |
Expense ratio | 37.70% | 38.40% | 38.80% | 39.50% |  |
Combined ratio | 97.40% | 100.00% | 97.70% | 98.50% |  |
Non-operating expenses related to Effectiveness and Efficiency Program | $ 8.6 |  | $ 20.4 |  |  |
Reinsurance |  |  |  |  |  |
Underwriting Revenues |  |  |  |  |  |
Gross written premiums | 326.0 | $ 335.6 | 949.5 | $ 900.9 |  |
Net written premiums | 266.9 | 285.5 | 691.9 | 733.7 |  |
Gross earned premiums | 366.2 | 320.6 | 741.2 | 648.2 |  |
Net earned premiums | 289.0 | 272.7 | 571.5 | 550.2 |  |
Underwriting Expenses |  |  |  |  |  |
Losses and loss adjustment expenses | 167.0 | 152.6 | 333.9 | 295.7 |  |
Amortization of deferred policy acquisition costs | 62.8 | 53.4 | 118.7 | 112.9 |  |
General and administrative expenses | 27.9 | 40.7 | 59.5 | 84.6 |  |
Underwriting income | 31.3 | 26.0 | 59.4 | 57.0 |  |
Net reserves for loss and loss adjustment expenses | $ 2,744.1 | $ 2,445.0 | $ 2,744.1 | $ 2,445.0 |  |
Ratios |  |  |  |  |  |
Loss ratio | 57.80% | 56.00% | 58.40% | 53.70% |  |
Policy acquisition expense ratio | 21.70% | 19.60% | 20.80% | 20.50% |  |
General and administrative expense ratio | 9.70% | 14.90% | 10.40% | 15.40% |  |
Expense ratio | 31.40% | 34.50% | 31.20% | 35.90% |  |
Combined ratio | 89.20% | 90.50% | 89.60% | 89.60% |  |
Insurance |  |  |  |  |  |
Underwriting Revenues |  |  |  |  |  |
Gross written premiums | $ 527.8 | $ 486.5 | $ 1,021.1 | $ 919.2 |  |
Net written premiums | 219.1 | 293.2 | 429.6 | 531.2 |  |
Gross earned premiums | 479.3 | 429.1 | 946.9 | 852.8 |  |
Net earned premiums | 230.5 | 289.3 | 481.5 | 592.9 |  |
Underwriting Expenses |  |  |  |  |  |
Losses and loss adjustment expenses | 143.4 | 193.5 | 286.7 | 378.6 |  |
Amortization of deferred policy acquisition costs | 23.1 | 42.9 | 58.0 | 97.1 |  |
General and administrative expenses | 57.2 | 65.7 | 120.8 | 127.5 |  |
Underwriting income | 6.8 | (12.8) | 16.0 | (10.3) |  |
Net reserves for loss and loss adjustment expenses | $ 2,132.3 | $ 2,347.0 | $ 2,132.3 | $ 2,347.0 |  |
Ratios |  |  |  |  |  |
Loss ratio | 62.20% | 66.90% | 59.50% | 63.90% |  |
Policy acquisition expense ratio | 10.00% | 14.80% | 12.00% | 16.40% |  |
General and administrative expense ratio | 24.80% | 22.70% | 25.10% | 21.50% |  |
Expense ratio | 34.80% | 37.50% | 37.10% | 37.90% |  |
Combined ratio | 97.00% | 104.40% | 96.60% | 101.80% |  |

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- Definition The difference between the price paid by the public and the contract price less the related expenses. A broker-dealer may underwrite a security offering by contracting to buy the issue either at a fixed price or a price based on selling the offering on a best-effort basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 605 -Section 05 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=68051933&loc=d3e44274-110985 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(b)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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