Variable Interest Entities (Narrative) (Details) $ in Millions	9 Months Ended
	Aug. 31, 2017 USD ($) joint_venture homes	Nov. 30, 2016 USD ($) joint_venture
Variable Interest Entity [Line Items]
Consolidated VIEs assets	$ 812.9	$ 536.3
Consolidated VIEs liabilities	$ 390.2	$ 126.4
Number of unconsolidated entities debt repayment guarantee | joint_venture	3	1
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Decrease in consolidated inventory	$ 265.6
Number of homesites sold | homes	475
Increase in consolidated inventory not owned resulting from consolidation	$ 320.1
Variable Interest Entity, Not Primary Beneficiary Including Third Parties
Variable Interest Entity [Line Items]
Non-refundable option deposits and pre-acquisition costs	144.4	$ 85.0
Financial Standby Letters of Credit | Variable Interest Entity, Not Primary Beneficiary Including Third Parties
Variable Interest Entity [Line Items]
Letters of credit outstanding	54.5	45.1
Lennar Multifamily | Equity Commitments | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Obligations to make capital contributions to VIEs	(182.1)	(288.2)
Lennar Multifamily | Financial Standby Letters of Credit | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Obligations to make capital contributions to VIEs	(13.0)	(19.7)
Lennar Homebuilding | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Obligations to make capital contributions to VIEs	$ (63.3)	$ (43.4)
Number of unconsolidated entities debt repayment guarantee | joint_venture	2