Debt Instrument, Accrued Interest and Payables, Fair Value Disclosure

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- Definition

Debt Instrument, Face Amount, Issued By Third Parties

+ References

No definition available.

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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

This item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets); the fair value of which assets and liabilities was or is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of direct and assumed premiums written.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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Fair Value Measurements - Loan Notes Issued by Variable Interest Entities (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross written premiums	$ 852.5	$ 763.5	$ 2,672.6	$ 2,540.9
Maximum \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross written premiums			57.6	43.4
Reserve for losses			$ 37.5	$ 11.8
Contract period			365 days	365 days
Loan notes held by third parties	(325.0)		$ (325.0)		$ (220.0)
Minimum \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross written premiums			50.1	$ 38.9
Reserve for losses			4.2	2.7
Loan notes held by third parties	(325.0)		(325.0)		(220.0)
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	7,555.6		7,555.6		7,653.6
Loan notes held by third parties	(101.5)		(101.5)		(115.0)
Loan notes issued by variable interest entities, at fair value (included within accrued expenses and other payables)	(2.4)		(2.4)		(108.4)
Fair Value, Measurements, Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	103.9		103.9		223.4
Loan notes held by third parties	(101.5)		(101.5)		(115.0)
Loan notes issued by variable interest entities, at fair value (included within accrued expenses and other payables)	(2.4)	$ (2.3)	(2.4)	$ (2.3)	(108.4)
Fair Value, Measurements, Recurring \| Level 3 \| Silverton 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	$ 103.9		$ 103.9
Fair Value, Measurements, Recurring \| Level 3 \| Silverton 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total					$ 223.4