Organization and Basis of Presentation (Detail) $ in Millions		6 Months Ended
Oct. 01, 2018 USD ($)	May 31, 2019 segment
Debt Instrument [Line Items]
Number of operating segments \| segment		2
Affiliated Entity \| Jefferies
Debt Instrument [Line Items]
Proceeds from contributions from parent	$ 598.2
Payment made in related party transaction	76.0
Related party transaction, related deferred tax liabilities transferred	$ 50.9
Berkadia Commercial Mortgage, LLC
Debt Instrument [Line Items]
Ownership percentage	50.00%

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Related Party Transaction, Related Deferred Tax Liabilities Transferred

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The cash inflow from parent as a source of financing that is recorded as additional paid in capital.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

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