Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Assets
Fixed maturity investments, trading, at fair value (Amortized cost 2018: $1,952.9; 2017: $2,195.3)	$ 1,949.2	$ 2,180.0
Short-term investments, at fair value (Amortized cost 2018: $716.1; 2017: $625.3)	715.5	625.0
Equity securities, trading, at fair value (Cost 2018: $409.4; 2017: $275.1)	380.0	299.2
Other long-term investments, at fair value (Cost 2018: $337.6; 2017: $255.5)	365.0	269.5
Cash	119.4	215.8
Restricted cash	12.8	14.8
Total investments and cash	3,541.9	3,604.3
Accrued investment income	14.1	14.1
Insurance and reinsurance premiums receivable	630.6	543.6
Reinsurance recoverable on unpaid losses	350.2	319.7
Reinsurance recoverable on paid losses	55.0	17.5
Funds held by ceding companies	186.8	153.2
Ceded unearned insurance and reinsurance premiums	159.8	106.6
Deferred acquisition costs	141.6	120.9
Deferred tax asset	202.5	244.1
Accounts receivable on unsettled investment sales	5.0	0.3
Goodwill	400.6	401.0
Intangible assets	195.6	216.3
Other assets	124.0	82.0
Total assets	6,007.7	5,823.6
Liabilities
Loss and loss adjustment expense reserves	2,016.7	1,898.5
Unearned insurance and reinsurance premiums	647.2	506.8
Ceded reinsurance payable	206.9	139.1
Funds held under reinsurance treaties	110.6	73.4
Deferred tax liability	237.4	282.2
Debt	696.8	723.2
Accounts payable on unsettled investment purchases	3.2	0.3
Other liabilities	150.5	176.8
Total liabilities	4,069.3	3,800.3
Commitments and Contingencies (see Note 22)
Mezzanine equity
Total mezzanine equity	232.2	106.1
Common shareholders' equity
Common shares (shares issued and outstanding: 2018: 115,151,251; 2017: 120,000,000)	1.2	1.2
Additional paid-in surplus	1,089.1	1,197.9
Retained earnings	816.6	858.4
Accumulated other comprehensive (loss)	(202.4)	(140.5)
Total common shareholders equity	1,704.5	1,917.0
Non-controlling interests	1.7	0.2
Total equity	1,706.2	1,917.2
Total liabilities, mezzanine equity, and equity	6,007.7	5,823.6
Series B preference shares
Mezzanine equity
Preference shares	$ 232.2
Series A redeemable preference shares
Mezzanine equity
Preference shares		$ 106.1

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Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Net amount of deferred policy acquisition costs capitalized on contracts remaining in force as of the balance sheet date.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Carrying amount of premiums written on insurance contracts that have not been earned as of the balance sheet date.

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