Commitments and Contingencies (Schedule of Expected Land and Lot Purchase Payments Under Option Agreements) (Details) $ in Thousands	Sep. 30, 2018 USD ($) lot	Dec. 31, 2017 lot
Commitments and Contingencies Disclosure [Abstract]
Lots under option \| lot	2,672	1,724
Remainder of 2018	$ 61,746
2019	134,550
2020	27,650
2021	12,244
2022	1,680
Total	$ 237,870

Land and Lots under Purchase Options, Expected Purchase Payments, Remainder of Fiscal Year

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Land and lots under Purchase Options, Expected Purchase Payments, Total

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Land and Lots under Purchase Options, Expected Purchase Payments, Year Five

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Land and lots under Purchase Options, Expected Purchase Payments, Year Four

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Land and lots under Purchase Options, Expected Purchase Payments, Year Three

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Land and lots under Purchase Options, Expected Purchase Payments, Year Two

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Lots under Purchase Options, Number

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