Summary of Significant Accounting Policies (Schedule Of The Company's Interests In Land Option Agreements) (Details) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
---|---|---|
Land under option agreement [Line Items] | ||
Deposits and Pre-acquisition Costs | $ 207,987 | $ 195,436 |
Remaining Purchase Price | 2,462,579 | 2,102,563 |
Other Land Option Agreements Member | ||
Land under option agreement [Line Items] | ||
Deposits and Pre-acquisition Costs | 129,098 | 126,909 |
Remaining Purchase Price | 1,485,099 | 1,252,662 |
Consolidated and Unconsolidated VIEs [Member] | ||
Land under option agreement [Line Items] | ||
Deposits and Pre-acquisition Costs | 78,889 | 68,527 |
Remaining Purchase Price | $ 977,480 | $ 849,901 |