Commitments And Contingencies (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012 site	May 12, 2010 property plaintiff	Nov. 07, 2008 plaintiff property	Oct. 24, 2008 plaintiff property	May 16, 2008 property plaintiff
Schedule Of Commitments And Contingencies [Line Items]
Surety bonds, issued and outstanding	$ 62.0
Letters of credit, issued and outstanding	19.1
Number of Plaintiffs		40	35	86	66
Number of Households		11	9	21	15
Right to acquire lots under Options Contracts, number of lots	1,464
HomeAmerican [Member]
Schedule Of Commitments And Contingencies [Line Items]
Letters of credit, issued and outstanding	6.2
Option Contracts [Member]
Schedule Of Commitments And Contingencies [Line Items]
Letters of credit, issued and outstanding	3.6
Cash deposits	$ 4.8