Summary of Significant Accounting Policies (Schedule Of The Company's Interests In Land Option Agreements) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Land under option agreement [Line Items]
Deposits and Pre-acquisition Costs	$ 299,437	$ 218,568
Remaining Purchase Price	3,221,962	2,602,410
Other Land Option Agreements Member
Land under option agreement [Line Items]
Deposits and Pre-acquisition Costs	175,662	127,851
Remaining Purchase Price	1,755,377	1,522,903
Consolidated and Unconsolidated VIEs [Member]
Land under option agreement [Line Items]
Deposits and Pre-acquisition Costs	123,775	90,717
Remaining Purchase Price	$ 1,466,585	$ 1,079,507