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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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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A valuation allowance for financing receivables that are expected to be uncollectible.

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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 of investments classified as other.

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Debt Obligations, net (Collateral Assets) (Details) - USD ($)	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Real estate, net	$ 1,771,019,000		$ 1,282,031,000
Real estate available and held for sale	22,551,000		68,588,000
Land and development, net	598,218,000		860,311,000
Loans receivable and other lending investments, net	988,224,000		1,300,655,000
Other investments	304,275,000	$ 397,110,000	321,241,000
Cash and other assets	1,329,990,000		898,252,000
Total assets	5,014,277,000	$ 4,806,947,000	4,731,078,000
Carrying amount of assets held by entities pledged as collateral	403,500,000
General reserves for loan losses	53,395,000		78,489,000		$ 85,545,000	$ 108,165,000
Loan participations	866,098,000		1,211,079,000
Loan Participations Payable
Debt Instrument [Line Items]
Loan participations			102,300,000
Collectively Evaluated for Impairment
Debt Instrument [Line Items]
General reserves for loan losses	13,000,000		17,500,000
Secured Debt \| 2015 $325 Million Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	325,000,000.0			$ 325,000,000.0
Collateral Assets
Debt Instrument [Line Items]
Real estate, net	1,620,008,000		795,321,000
Real estate available and held for sale	1,055,000		20,069,000
Land and development, net	12,300,000		25,100,000
Loans receivable and other lending investments, net	498,524,000		194,529,000
Other investments	0		0
Cash and other assets	0		0
Total assets	2,131,887,000		1,035,019,000
Non-Collateral Assets
Debt Instrument [Line Items]
Real estate, net	151,011,000		486,710,000
Real estate available and held for sale	21,496,000		48,519,000
Land and development, net	585,918,000		835,211,000
Loans receivable and other lending investments, net	480,154,000		1,021,340,000
Other investments	304,275,000		321,241,000
Cash and other assets	1,329,990,000		898,252,000
Total assets	$ 2,872,844,000		$ 3,611,273,000