Inventories - Summary of Inventory (Details) - Homebuilding Segment - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory [Line Items]
Housing completed or under construction	$ 1,486,587	$ 1,036,191
Land and land under development	1,345,643	1,330,384
Total inventories	2,832,230	2,366,575
West
Inventory [Line Items]
Housing completed or under construction	902,842	589,040
Land and land under development	822,504	772,189
Mountain
Inventory [Line Items]
Housing completed or under construction	464,501	358,370
Land and land under development	391,054	468,718
East
Inventory [Line Items]
Housing completed or under construction	119,244	88,781
Land and land under development	$ 132,085	$ 89,477

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
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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
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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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