Amount received from former executives to repay loans and retention awards.

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Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]

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Micro captive Insurance Companies Managed

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Number of employees resigned.

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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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

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Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

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Commitments, Contingencies and Off-Balance Sheet Arrangements - Litigation, Regulatory and Taxation Matters- Additional Information (Detail) £ in Millions, $ in Millions			12 Months Ended
	Aug. 26, 2015 USD ($)	Aug. 26, 2015 GBP (£)	Dec. 31, 2015 USD ($) Employees Companies
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Litigation payments	$ 31.0	£ 20.0
Amount received from former executives	$ 3.1	£ 2.0
Pretax gain related to litigation settlement \| $			$ 31.0
United Kingdom [Member] \| Brokerage [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Number of senior employees resigned \| Employees			5
Minimum [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Number of micro-captive insurance companies organized or managed \| Companies			100