Amount of consideration transferred for the purchase of real estate.

No definition available.

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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI https://asc.fasb.org/extlink&oid=126905981&loc=d3e2443-110228

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

+ Details

Name:	us-gaap_NotesPayable
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow from the acquisition of residential property intended to generate income for the owner.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3213-108585

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Cash received for the sale of real estate that is not part of an investing activity during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3179-108585

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_DisposalGroupClassificationAxis=us-gaap_SegmentDiscontinuedOperationsMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=sqft_ModelHomeMember
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Balance Type:
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- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Note 3 - Recent Real Estate Transactions (Details Textual)			3 Months Ended
	Feb. 19, 2021 USD ($)	Jan. 28, 2021 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Notes Payable, Total					$ 0
Discontinued Operations [Member]
Number of Real Estate Properties			11	12
Proceeds from Sale of Real Estate			$ 5,600,000	$ 4,900,000
Gain (Loss) on Sale of Properties			$ 1,800,000	$ 400,000
Model Home [Member]
Number of Real Estate Properties			4
Real Estate Property, Consideration Transferred, Total			$ 2,400,000
Payments to Acquire Residential Real Estate			700,000
Notes Payable, Total			1,700,000
Waterman Plaza [Member] \| Discontinued Operations [Member]
Proceeds from Sale of Real Estate			10,000,000.0
Gain (Loss) on Sale of Properties			$ (300,000)
Waterman Plaza [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Proceeds from Sale of Real Estate		$ 3,500,000
Gain (Loss) on Sale of Properties		$ (200,000)
Garden Gateway [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Proceeds from Sale of Real Estate	$ 11,200,000
Gain (Loss) on Sale of Properties	$ (1,400,000)