Variable Interest Entities (Details) (USD $) In Millions	Aug. 31, 2011	Nov. 30, 2010
Variable Interest Entities (Textuals) [Abstract]
Cash deposits associated with land option and other similar contracts of unconsolidated VIE's	$ 2.6	$ 2.6
Aggregate purchase price of land option and other similar contracts of unconsolidated VIE's	110.6	86.1
Total cash deposits associated with land option and other similar contracts that were not VIE's	13.0	12.2
Aggregate purchase price of land option and other similar contracts that were not VIE's	219.3	274.3
Non-Refundable Cash Deposits on Land Option and Other Similar Contracts	15.6	14.8
Outstanding letters of credit	2.0	4.2
Increase in inventories and accrued expenses and other liabilities	$ 25.1	$ 15.5

Cash Deposits Associated With Land Option And Other Similar Contracts Of Non Variable Interest Entities.

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Cash Deposits Associated With Land Option And Other Similar Contracts Of Unconsolidated Variable Interest Entities.

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Increase In Inventories And Accrued Expenses And Other Liabilities Due To Land Option And Other Similar Contracts.

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Non-Refundable Cash Deposits on Land Option and Other Similar Contracts.

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Outstanding Letters Of Credit In Lieu Of Cash Deposits Under Certain Land Option Or Other Similar Contracts.

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Purchase Price Associated With Land Option And Other Similar Contracts Of Non Variable Interest Entities.

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Purchase Price Associated With Land Option And Other Similar Contracts Of Unconsolidated Variable Interest Entities.

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Variable Interest Entities.

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