The area of office space leased.

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Period between issuance and maturity of investment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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No definition available.

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Period of extension for investment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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The number of additional properties under management during the period.

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No definition available.

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Represents the annual base rent per square foot under the operating leases.

+ References

No definition available.

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Represents the percentage of increase in annual base rent under the operating leases.

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No definition available.

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Number of renewal options for the investment loan.

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No definition available.

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- Definition

Rate of interest on investment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount of increase in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from new investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

The cash outflow associated with extending a long-term loan to a related party. Alternate caption: Payments for Advances to Affiliates.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

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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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No definition available.

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The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

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Related-Party Transactions - Investments in Loans and Securities and Other Arrangements (Details) $ in Thousands, € in Millions	1 Months Ended				3 Months Ended
	Mar. 31, 2020 USD ($) ft² $ / ft²	Feb. 29, 2020 USD ($) Option	Jan. 31, 2020 EUR (€)	Jan. 31, 2020 USD ($)	Mar. 31, 2020 USD ($) property	Mar. 31, 2019 USD ($)	Apr. 30, 2020 USD ($)
Related-Party Transactions
Acquisitions and originations of mortgage financing					$ 1,898,905	$ 2,027,669
SEREF \| Mezzanine Loans
Related-Party Transactions
Payments to Fund Long-term Loans to Related Parties \| €			€ 70.3
Acquisitions and originations of mortgage financing \| €			€ 35.2
Highmark Residential
Related-Party Transactions
Number of additional properties under management \| property					21
Payments to related party					$ 500	$ 300
Affiliates of Manager \| Origination Of Loan For Development And Recapitalization Of Luxury Cabin Rentals
Related-Party Transactions
Payments to Fund Long-term Loans to Related Parties				$ 3,500
Affiliates of Manager \| Origination Of First Mortgage Loan
Related-Party Transactions
Payments to Fund Long-term Loans to Related Parties		$ 99,000
Interest rate		10.50%
Term		36 months
Number of options \| Option		2
Renewal term		1 year
Affiliates Of Chairman And CEO \| Office Lease Agreement With Affiliate Of Chairman And CEO
Related-Party Transactions
Area of office space \| ft²	74,000
Lease Term	15 years				15 years
Operating Lease, Annual Base Rent Per Square Foot \| $ / ft²	52.00
Operating Lease, Percentage Of Increase in Annual Base Rent	3.00%
Security Deposit							$ 1,900
Loans held-for-sale, residential \| Residential mortgage originator
Related-Party Transactions
Acquisitions and originations of mortgage financing					$ 100,800
Purchase Commitment, Remaining Minimum Amount Committed	$ 18,000				$ 18,000