Inventories - Summary of Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Inventory [Line Items]
Housing completed or under construction	$ 1,705,424	$ 1,486,587
Land and land under development	1,310,721	1,345,643
Total inventories	3,016,145	2,832,230
Homebuilding:
Inventory [Line Items]
Housing completed or under construction	1,705,424	1,486,587
Land and land under development	1,310,721	1,345,643
Total inventories	3,016,145	2,832,230
Homebuilding: \| West
Inventory [Line Items]
Housing completed or under construction	1,018,436	902,842
Land and land under development	788,753	822,504
Homebuilding: \| Mountain
Inventory [Line Items]
Housing completed or under construction	547,831	464,501
Land and land under development	380,923	391,054
Homebuilding: \| East
Inventory [Line Items]
Housing completed or under construction	139,157	119,244
Land and land under development	$ 141,045	$ 132,085

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Subparagraph (SX 210.5-02.6(a))
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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Carrying amount as of the balance sheet date, net of valuation allowances and impairment losses, of costs of land expected to be developed in the near term plus capitalized costs of development, for purposes of selling completed units to home buyers or commercial or industrial entities..

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