Sum of all assets excluding the Company's Total Portfolio Assets.

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Collateral Assets, Assets Held By Entities Pledged As Collateral, Carrying Amount

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Amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among myriad other features and characteristics. In addition, amount also includes total debt and equity financial instruments including: securities held-to-maturity and securities available-for-sale.

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Carrying amount as of the balance sheet date of investments in land and buildings held for sale, including real estate considered to be inventory of the entity.

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Real Estate Investment Property, Held for Use, Net

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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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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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of investments classified as other.

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Debt Obligations, net (Encumbered/Unencumbered Assets) (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Mar. 31, 2015
Debt Instrument [Line Items]
Real estate, net	$ 1,893,789,000	$ 1,282,031,000
Real estate available and held for sale	61,549,000	68,588,000
Land and development, net	650,531,000	860,311,000
Loans receivable and other lending investments, net	1,029,052,000	1,300,655,000
Other investments	302,318,000	321,241,000
Cash and other assets	1,142,750,000	898,252,000
Total assets	5,079,989,000	4,731,078,000
Carrying amount of assets held by entities pledged as collateral	410,400,000
Loans receivable, net	909,280,000	1,211,079,000
Loan participations payable, net
Debt Instrument [Line Items]
Loans receivable, net	18,400,000	102,300,000
Collectively Evaluated for Impairment
Debt Instrument [Line Items]
General reserves for loan losses	14,300,000	17,500,000
2015 $325 million Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	325,000,000		$ 325,000,000	$ 250,000,000.0
Collateral Assets
Debt Instrument [Line Items]
Real estate, net	1,570,920,000	795,321,000
Real estate available and held for sale	31,145,000	20,069,000
Land and development, net	17,500,000	25,100,000
Loans receivable and other lending investments, net	499,895,000	194,529,000
Other investments	0	0
Cash and other assets	6,398,000	0
Total assets	2,125,858,000	1,035,019,000
Non-Collateral Assets
Debt Instrument [Line Items]
Real estate, net	322,869,000	486,710,000
Real estate available and held for sale	30,404,000	48,519,000
Land and development, net	633,031,000	835,211,000
Loans receivable and other lending investments, net	525,103,000	1,021,340,000
Other investments	302,318,000	321,241,000
Cash and other assets	1,136,352,000	898,252,000
Total assets	$ 2,950,077,000	$ 3,611,273,000