Inventory (Summary of Interests in Land Option Agreements) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Variable Interest Entity [Line Items]
Deposits and Pre-acquisition Costs	$ 183,031	$ 162,119
Remaining Purchase Price	2,287,112	2,046,193
Land options with VIEs
Variable Interest Entity [Line Items]
Deposits and Pre-acquisition Costs	91,777	77,641
Remaining Purchase Price	1,152,369	1,064,506
Other Land Option Agreements Member
Variable Interest Entity [Line Items]
Deposits and Pre-acquisition Costs	91,254	84,478
Remaining Purchase Price	$ 1,134,743	$ 981,687