Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)(1)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of the cumulative effect on retained earnings net of related income tax effect.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 250

-SubTopic 10

-Section 50

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=28359718&loc=d3e22663-107794

+ Details

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Redeemable Noncontrolling Interest - Additional Information (Detail) (Trident [Member], USD $)	3 Months Ended	12 Months Ended				0 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Northshore [Member]	Mar. 31, 2014 Northshore [Member] Atrium [Member]	Mar. 31, 2014 Northshore [Member] Arden [Member]	Mar. 30, 2014 Bayshore [Member]	Mar. 31, 2014 Bayshore [Member]	Mar. 31, 2014 Bayshore [Member] Torus Insurance Holdings Limited [Member]
Redeemable Noncontrolling Interest [Line Items]
Interest owned by an entity			40.00%	100.00%	100.00%		40.00%	100.00%
Adjustments recorded through retained earnings	$ 0	$ 0
Contribution for share held						$ 260,800,000