Significant Accounting Policies (Schedule of Real Estate Inventory) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Capital Leases, Net Investment in Direct Financing Leases, Interest Rate Maximum	12.00%
Completed home inventory and residential lots held for sale	$ 106,043	$ 127,679
Work in process and land under development	389,612	269,255
Undeveloped land	0	4,070
Land not owned under option contracts	0	9,293
Inventory, Real Estate	$ 495,655	$ 410,297

Capital Leases, Net Investment in Direct Financing Leases, Interest Rate Maximum

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- Definition

Inventory, Finished Homes and Land Held for Sale

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- Definition

Carrying amount as of the balance sheet date of capitalized construction costs of homes for future sale and costs of land expected to be developed in the near term.

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No definition available.

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- Definition

The net carrying amount as of the balance sheet date of the sum of the various components of an operative builder's inventory, including finished homes. Operative builders primarily consist of entities that develop land, construct residential homes and commercial and industrial buildings thereon, and sell them to home buyers and operators of the commercial and industrial properties.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of inventory used in the development of real estate classified as other.

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- Definition

The carrying amount as of the balance sheet date of land not owned but under a contract in which the entity has an option to purchase the land.

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