Inventories - Summary of Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Inventory [Line Items]
Housing completed or under construction	$ 1,872,666	$ 1,486,587
Land and land under development	1,309,360	1,345,643
Total inventories	3,182,026	2,832,230
Homebuilding:
Inventory [Line Items]
Housing completed or under construction	1,872,666	1,486,587
Land and land under development	1,309,360	1,345,643
Total inventories	3,182,026	2,832,230
Homebuilding: \| West
Inventory [Line Items]
Housing completed or under construction	1,064,028	902,842
Land and land under development	838,482	822,504
Homebuilding: \| Mountain
Inventory [Line Items]
Housing completed or under construction	608,629	464,501
Land and land under development	325,277	391,054
Homebuilding: \| East
Inventory [Line Items]
Housing completed or under construction	200,009	119,244
Land and land under development	$ 145,601	$ 132,085

Carrying amount as of the balance sheet date of capitalized construction costs of homes for future sale.

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