Goodwill and Other Intangible Assets (Schedule of Finite-Lived Intangible Assets by Major Class) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	58,399	$ 58,477
Accumulated amortization and impairment losses	(43,424)	(39,560)
Other intangible assets, Net	14,975	18,917
Customer relationships and customer lists
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	40,562	40,640
Accumulated amortization and impairment losses	(28,057)	(24,522)
Other intangible assets, Net	12,505	16,118
Lloyd's managing agency license
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	1,867	1,867
Accumulated amortization and impairment losses	0	0
Other intangible assets, Net	1,867	1,867
Trademarks and trade names
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	610	610
Accumulated amortization and impairment losses	(159)	(134)
Other intangible assets, Net	451	476
Covenants not-to-compete
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	2,130	2,130
Accumulated amortization and impairment losses	(1,978)	(1,674)
Other intangible assets, Net	152	456
Software
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	8,730	8,730
Accumulated amortization and impairment losses	(8,730)	(8,730)
Other intangible assets, Net	0	0
Patents and intellectual property
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	4,500	4,500
Accumulated amortization and impairment losses	(4,500)	(4,500)
Other intangible assets, Net	0	$ 0
Minimum
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, useful life	1 year
Maximum
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, useful life	25 years
Weighted Average
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, useful life	11 years

Intangible Assets (Excluding Goodwill), Accumulated Amortization and Impairment

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

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