v3.21.1

Loans Held for Investment - Loan Portfolio Statistics (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($) loan
Receivables [Abstract]
Number of Loans \| loan	13	14
Total loan commitments	$ 268,379	$ 293,890
Unfunded loan commitments	8,989	12,236
Principal balance	259,390	281,654
Unamortized net deferred origination and exit fees	789	592
Carrying value	$ 260,179	$ 282,246
Weighted average coupon rate	5.73%	5.70%
Weighted average all in yield	6.43%	6.39%
Weighted average maximum maturity (years)	2 years 4 months 24 days	2 years 7 months 6 days
Weighted average risk rating	2.9	3.2
Weighted average LTV	0.67	0.67

Amount of contractual principal due at origination of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column F
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column F))
-URI http://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

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- Definition

Number of mortgage loans within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Footnote 3
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Footnote 3))
-URI http://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

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- Definition

Financing Receivable, Unfunded Loan Commitments

+ References

No definition available.

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- Definition

Loan Receivable, Loan-To-Value Ratio, Percentage

+ References

No definition available.

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- Definition

Loans Held-For-Investment, Commitments

+ References

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- Definition

Loans Receivable, Average All-In Yield, Percentage

+ References

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- Definition

Loans Receivable, Weighted Average Coupon Rate, Percentage

+ References

No definition available.

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- Definition

Loans Receivable, Weighted Average Term Of Maturity

+ References

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- Definition

Mortgage Loans On Real Estate, Weighted Average Risk Rating Of Portfolio

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G))
-URI http://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

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- References

No definition available.

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- Definition

Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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Tremont Mortgage Trust 10-Q