Summary of Significant Accounting Policies (Detail) - USD ($) $ in Millions	12 Months Ended
Nov. 30, 2016	Nov. 30, 2015	Nov. 30, 2014
Summary Of Significant Accounting Policies [Line Items]
Furniture, fixtures and equipment under capital leases	$ 374.2	$ 365.8
Leasehold improvements	200.5	190.5
Accumulated depreciation and amortization	309.2	312.8
Depreciation and amortization	$ 47.9	$ 78.7	$ 58.0
Percentage of tax benefit realized upon ultimate settlement with taxing authority	50.00%
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life of premises and equipment	3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life of premises and equipment	10 years

Percentage Of Tax Benefit Realized Upon Ultimate Settlement With Taxing Authority

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Summary Of Significant Accounting Policies [Line Items]

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 45
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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