Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due within 1 year (or 1 business cycle).

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Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Related Party Transactions (Details) - Affiliated Entity - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Materials & Construction \| Supplier Contracts
Related Party Transaction [Line Items]
Revenue from related parties	$ 3,800,000	$ 2,800,000	$ 5,800,000	$ 9,600,000
Expenses recognized from transactions with affiliates	(200,000)	100,000	1,100,000	100,000
Receivables from related parties	1,100,000		1,100,000		$ 200,000
Payables to related parties	1,000,000.0		1,000,000.0		1,200,000
Real estate leasing and development \| Lease Agreements
Related Party Transaction [Line Items]
Revenue from related parties			0	1,300,000
Land Operations \| Service revenues and Interest
Related Party Transaction [Line Items]
Revenue from related parties	300,000	$ 1,100,000	1,400,000	$ 1,700,000
Receivables from related parties	100,000		100,000		100,000
Land Operations \| Extension of Secured Note Receivable
Related Party Transaction [Line Items]
Receivable from affiliate	$ 9,800,000		$ 9,800,000		$ 13,100,000