Inventories - Summary of Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Inventory [Line Items]
Housing completed or under construction	$ 1,423,855	$ 1,036,191
Land and land under development	1,221,854	1,330,384
Total inventories	2,645,709	2,366,575
Homebuilding:
Inventory [Line Items]
Housing completed or under construction	1,423,855	1,036,191
Land and land under development	1,221,854	1,330,384
Total inventories	2,645,709	2,366,575
Homebuilding: \| West
Inventory [Line Items]
Housing completed or under construction	844,264	589,040
Land and land under development	698,099	772,189
Homebuilding: \| Mountain
Inventory [Line Items]
Housing completed or under construction	463,690	358,370
Land and land under development	412,299	468,718
Homebuilding: \| East
Inventory [Line Items]
Housing completed or under construction	115,901	88,781
Land and land under development	$ 111,456	$ 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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