The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

The carrying amount of investments in unconsolidated real estate and other joint ventures not separately presented. This includes direct and indirect investments.

+ 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 210.7-03.1(d))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

Name:	us-gaap_RealEstateInvestmentsUnconsolidatedRealEstateAndOtherJointVentures
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=sor_OcmNipJvHoldingsLPAndHcKbsNipJvLlcHcKbsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=sor_A110WilliamJointVentureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=sor_A353SacramentoJointVentureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=sor_BatteryPointSeriesA3PreferredUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=sor_PacificOakOpportunityZoneFundIMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Investments in Unconsolidated Joint Ventures) (Details) $ in Thousands	Dec. 31, 2019 USD ($) property	Dec. 31, 2018 USD ($)	May 02, 2014
Schedule of Equity Method Investments [Line Items]
Investment Balance	$ 78,276	$ 44,869
NIP Joint Venture
Schedule of Equity Method Investments [Line Items]
Number of Properties \| property	2
Investment Balance	$ 1,225	1,476
NIP Joint Venture \| Maximum
Schedule of Equity Method Investments [Line Items]
Ownership %	5.00%
110 William Joint Venture
Schedule of Equity Method Investments [Line Items]
Number of Properties \| property	1
Ownership %	60.00%		60.00%
Investment Balance	$ 0	325
353 Sacramento Joint Venture
Schedule of Equity Method Investments [Line Items]
Number of Properties \| property	1
Ownership %	55.00%
Investment Balance	$ 42,214	43,068
Battery Point Series A-3 Preferred Units
Schedule of Equity Method Investments [Line Items]
Investment Balance	$ 13,991	0
Pacific Oak Opportunity Zone Fund I
Schedule of Equity Method Investments [Line Items]
Number of Properties \| property	2
Investment Balance	$ 20,846	$ 0