Description of the terms of a settlement agreement which resolved the legal matter, including the nature of the consideration, timing of payment, and the nature of rights obtained or lost (for example, but not limited to, patent, trademark, copyright, license and franchise rights).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Significant New Business - Additional Information (Detail) In Millions, unless otherwise specified	3 Months Ended				3 Months Ended
	Mar. 31, 2014 USD ($)	Mar. 31, 2014 GBP (£)	Dec. 31, 2013 USD ($)	Dec. 31, 2013 GBP (£)	Mar. 31, 2014 Reciprocal of America [Member] Reinsurance Agreement under 2014 [Member]	Jul. 06, 2012 Reciprocal of America [Member] Reinsurance Agreement under 2014 [Member] USD ($)
Business Acquisition [Line Items]
Total assets and assumed gross reinsurance reserves received						$ 169.0
Expected closing period of transaction					Second quarter of 2014
Gross insurance reserves	$ 313.3	£ 193.0	$ 28.1	£ 17.0
Percentage of reinsurance agreement	100.00%	100.00%