Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Mortgages Receivable - Additional information (Details)

v3.21.1

Mortgages Receivable - Additional information (Details)	12 Months Ended
Mortgages Receivable - Additional information (Details)	Dec. 31, 2020 USD ($) loan STD (Db)	Dec. 31, 2019 USD ($) loan	Jun. 30, 2020 USD ($) loan
Mortgage Loans on Real Estate, Default Interest Rate	18.00%
Payments to Acquire Mortgage Receivable	$ 117,230,923	$ 64,742,552
Proceeds from Collection of Mortgages Receivable	54,961,570	43,347,362
Mortgages receivable	$ 155,616,300	$ 94,348,689
Mortgage loan portfolio number of loans	495	438
Mortgage loan portfolio number of loans in process of foreclosure \| Db	16
Number of COVID-19 forbearance requests \| loan	0		23
Mortgages receivable for COVID-19 forbearance requests			$ 6,500,000
Deferred interest			$ 200,000
Mortgage Concentration Risk [Member]
Concentration Risk, Percentage	10.00%	10.00%
Mortgages [Member]
Payments to Acquire Mortgage Receivable	$ 117,230,923	$ 64,742,552
Minimum [Member]
Debt term (in years)	1 year
Mortgage Loans on Real Estate, Face Amount of Mortgages	$ 2,600
Interest rate (as a percent)	5.00%
Maximum [Member]
Debt term (in years)	3 years
Mortgage Loans on Real Estate, Face Amount of Mortgages	$ 10,780,000
Interest rate (as a percent)	13.00%
Nine Mortgage Loans [Member]
Mortgages receivable	$ 3,100,000
Thirteen Mortgage Loans [Member]
Mortgages receivable		$ 2,800,000
Mortgage loan portfolio number of loans in process of foreclosure \| loan		9

- Definition

Deferred interest for COVID-19 forbearance requests.

+ References

No definition available.

+ Details

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- Definition

Mortgage loan receivables on COVID-19 forbearance requests.

+ References

No definition available.

+ Details

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Namespace Prefix:	sach_
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- Definition

Mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

No definition available.

+ Details

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Namespace Prefix:	sach_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The default interest rate on the mortgage loan receivable.

+ References

No definition available.

+ Details

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Namespace Prefix:	sach_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of mortgage receivable for COVID-19 forbearance requests.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The cash outflow to acquire a mortgage receivable for a definite sum of money at a future date.

+ References

No definition available.

+ Details

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Namespace Prefix:	sach_
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Balance Type:	credit
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- Definition

The cash inflow associated with principal collections from a mortgages receivable.

+ References

No definition available.

+ Details

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Namespace Prefix:	sach_
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- Definition

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

Interest rate 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 B
-Subsection 29

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-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column B))
-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

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599

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- Definition

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

+ References

No definition available.

+ Details

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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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