Lennar Multifamily (Narrative) (Details)	1 Months Ended	3 Months Ended
	Mar. 31, 2018 USD ($) apartment asset	Feb. 28, 2018 USD ($)	Feb. 28, 2017 USD ($)	Nov. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Distributions of capital from unconsolidated entities		$ 20,927,000	$ 39,961,000
Lennar Multifamily
Segment Reporting Information [Line Items]
Non-recourse debt with completion guarantees		977,100,000		$ 896,700,000
General Contractor Revenue		81,700,000	75,700,000
General Contractor Costs		78,600,000	73,700,000
Investments in unconsolidated entities		437,367,000		407,544,000
Lennar Multifamily | Variable Interest Entity, Not Primary Beneficiary | Equity Commitments
Segment Reporting Information [Line Items]
Obligations related to VIEs		121,600,000		153,300,000
Lennar Multifamily | Lennar Multifamily Venture
Segment Reporting Information [Line Items]
Total equity commitments		2,200,000,000
Equity commitments		504,000,000
Equity commitments called during period		131,900,000
Equity commitment contributions during period			31,700,000
Distributions of capital from unconsolidated entities			900,000
Equity Commitments Called		1,600,000,000
Funds contributed by the company		382,400,000
Investments in unconsolidated entities		353,400,000		323,800,000
Lennar Multifamily | Unconsolidated Entities
Segment Reporting Information [Line Items]
Fee Income		11,500,000	$ 13,000,000.0
Lennar Multifamily | Financial Letters of Credit
Segment Reporting Information [Line Items]
Letters of credit outstanding		$ 4,600,000		$ 4,700,000
Subsequent Event | Lennar Multifamily | Lennar Multifamily Venture II LP
Segment Reporting Information [Line Items]
Total equity commitments	$ 500,000,000
Equity commitments	$ 255,000,000
Number of assets transferred | asset	6
Number of apartments | apartment	2,200
Projected project costs	$ 900,000,000