Pacific Oak Strategic Opportunity REIT (PCOK) 10-Q 14 Nov 17 2017 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Nov. 09, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	KBS Strategic Opportunity REIT, Inc.
Entity Central Index Key	1,452,936
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		52,107,629

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Assets
Real estate held for investment, net	$ 1,045,671	$ 1,060,098
Real estate held for sale, net	0	46,933
Real estate equity securities	47,022	0
Real estate debt securities, net	17,642	4,683
Total real estate and real estate-related investments, net	1,110,335	1,111,714
Cash and cash equivalents	97,487	40,432
Restricted cash	16,086	24,018
Investments in unconsolidated joint ventures	58,329	75,849
Rents and other receivables, net	30,252	27,521
Above-market leases, net	395	618
Assets related to real estate held for sale, net	0	1,488
Prepaid expenses and other assets	31,469	28,476
Total assets	1,344,353	1,310,116
Notes and bonds payable, net
Notes and bonds payable related to real estate held for investment, net	990,248	919,174
Notes payable related to real estate held for sale, net	0	31,450
Total notes and bonds payable, net	990,248	950,624
Accounts payable and accrued liabilities	27,473	26,624
Due to affiliate	33	55
Below-market leases, net	3,751	6,029
Liabilities related to real estate held for sale, net	0	522
Other liabilities	21,904	18,095
Redeemable common stock payable	11,386	12,617
Total liabilities	1,054,795	1,014,566
Commitments and contingencies (Note 14)
Redeemable common stock	52,000	0
Equity
Preferred stock, $.01 par value per share; 10,000,000 shares authorized, no shares issued and outstanding	0	0
Common stock, $.01 par value per share; 1,000,000,000 shares authorized, 56,795,632 and 56,775,767 shares issued and outstanding as of September 30, 2017 and December 31, 2016, respectively	568	568
Additional paid-in capital	405,220	455,373
Cumulative distributions and net losses	(173,964)	(162,289)
Accumulated other comprehensive income	3,714	0
Total KBS Strategic Opportunity REIT, Inc. stockholders’ equity	235,538	293,652
Noncontrolling interests	2,020	1,898
Total equity	237,558	295,550
Total liabilities and equity	$ 1,344,353	$ 1,310,116

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	56,795,632	56,775,767
Common stock, shares outstanding (in shares)	56,795,632	56,775,767

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues:
Rental income	$ 27,850	$ 29,229	$ 90,200	$ 76,646
Tenant reimbursements	6,094	5,902	18,188	15,484
Other operating income	944	1,002	3,484	2,580
Interest income from real estate debt securities	511	0	1,271	0
Dividend income from real estate equity securities	1,015	0	1,505	0
Interest income from real estate loan receivable	0	0	0	3,655
Total revenues	36,414	36,133	114,648	98,365
Expenses:
Operating, maintenance, and management	11,431	10,932	33,638	29,755
Real estate taxes and insurance	4,780	4,516	14,932	12,419
Asset management fees to affiliate	2,800	2,639	8,404	6,932
Real estate acquisition fees to affiliate	0	1,690	0	2,964
Real estate acquisition fees and expenses	0	274	0	542
General and administrative expenses	1,170	1,337	4,291	4,172
Foreign currency transaction loss, net	4,356	6,639	11,454	4,602
Depreciation and amortization	13,228	14,337	43,136	37,436
Interest expense	9,618	7,992	29,327	20,354
Total expenses	47,383	50,356	145,182	119,176
Other income (loss):
Income from unconsolidated joint venture	0	0	1,869	0
Other interest income	340	7	536	22
Equity in loss of unconsolidated joint ventures	(2,152)	(791)	(3,928)	(1,139)
Gain on sale of real estate	2,239	0	36,267	0
Total other income (loss), net	427	(784)	34,744	(1,117)
Net (loss) income	(10,542)	(15,007)	4,210	(21,928)
Net loss attributable to noncontrolling interests	8	56	10	124
Net (loss) income attributable to common stockholders	$ (10,534)	$ (14,951)	$ 4,220	$ (21,804)
Net (loss) income per common share, basic and diluted (in dollars per share)	$ (0.19)	$ (0.25)	$ 0.07	$ (0.37)
Weighted-average number of common shares outstanding, basic and diluted (in shares)	56,643,160	58,642,752	56,712,752	58,676,546

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (10,542)	$ (15,007)	$ 4,210	$ (21,928)
Other comprehensive income:
Unrealized gain on real estate securities	2,865	0	3,714	0
Total other comprehensive income	2,865	0	3,714	0
Total comprehensive (loss) income	(7,677)	(15,007)	7,924	(21,928)
Total comprehensive loss attributable to noncontrolling interests	8	56	10	124
Total comprehensive (loss) income attributable to common stockholders	$ (7,669)	$ (14,951)	$ 7,934	$ (21,804)

CONSOLIDATED STATEMENTS OF EQUI

CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Total Stockholders' Equity	Common Stock	Additional Paid-in Capital	Cumulative Distributions and Net Losses	Accumulated Other Comprehensive Income	Noncontrolling Interests
Balance (in shares) at Dec. 31, 2015			58,696,115
Balance at Dec. 31, 2015	$ 408,790	$ 393,363	$ 587	$ 504,303	$ (111,527)	$ 0	$ 15,427
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(29,126)	(28,918)			(28,918)		(208)
Issuance of common stock (in shares)			938,662
Issuance of common stock	12,616	12,616	$ 9	12,607
Transfers from redeemable common stock	957	957		957
Redemptions of common stock (in shares)			(2,859,010)
Redemptions of common stock	(38,573)	(38,573)	$ (28)	(38,545)
Distributions declared	(21,844)	(21,844)			(21,844)
Acquisitions of noncontrolling interests	(37,986)	(23,942)		(23,942)			(14,044)
Other offering costs	(7)	(7)		(7)
Noncontrolling interests contributions	803						803
Distributions to noncontrolling interests	$ (80)						(80)
Balance (in shares) at Dec. 31, 2016	56,775,767		56,775,767
Balance at Dec. 31, 2016	$ 295,550	293,652	$ 568	455,373	(162,289)	0	1,898
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	4,210	4,220			4,220		(10)
Other comprehensive income	3,714	3,714				3,714
Issuance of common stock (in shares)			585,192
Issuance of common stock	8,666	8,666	$ 6	8,660
Transfers to redeemable common stock	(50,769)	(50,769)		(50,769)
Redemptions of common stock (in shares)			(565,327)
Redemptions of common stock	(8,050)	(8,050)	$ (6)	(8,044)
Distributions declared	(15,895)	(15,895)			(15,895)
Noncontrolling interests contributions	150						150
Distributions to noncontrolling interests	$ (18)						(18)
Balance (in shares) at Sep. 30, 2017	56,795,632		56,795,632
Balance at Sep. 30, 2017	$ 237,558	$ 235,538	$ 568	$ 405,220	$ (173,964)	$ 3,714	$ 2,020

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Cash Flows from Operating Activities:
Net income (loss)	$ (10,542)	$ (15,007)	$ 4,210	$ (21,928)	$ (29,126)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Loss due to property damages			668	2,017
Equity in loss of unconsolidated joint ventures	2,152	791	3,928	1,139
Depreciation and amortization	13,228	14,337	43,136	37,436
Gain on real estate	(2,239)	0	(36,267)	0
Unrealized loss on interest rate caps			102	0
Deferred rent			(1,678)	(2,020)
Bad debt expense			66	488
Amortization of above- and below-market leases, net			(2,253)	(1,375)
Amortization of deferred financing costs	1,000	1,100	3,578	2,908
Interest accretion on real estate debt securities			(456)	0
Net amortization of discount and (premium) on bond and notes payable			36	28
Foreign currency transaction loss, net	4,356	6,639	11,454	4,602
Changes in assets and liabilities:
Rents and other receivables			(2,245)	(2,656)
Prepaid expenses and other assets			(6,368)	(7,255)
Accounts payable and accrued liabilities			1,575	3,950
Due to affiliates			(22)	(8)
Other liabilities			261	2,700
Net cash provided by operating activities			19,725	20,026
Cash Flows from Investing Activities:
Acquisitions of real estate			(165,465)	(293,831)
Improvements to real estate			(28,775)	(21,466)
Proceeds from sales of real estate, net			130,580	0
Principal proceeds from assignment of real estate loan receivable			0	27,850
Insurance proceeds received for property damages			744	1,767
Purchase of interest rate cap			(107)	0
Purchase of foreign currency option			(3,434)	0
Proceeds from termination of foreign currency collars			6,557	0
Investment in unconsolidated joint venture			0	(2,820)
Distributions of capital from unconsolidated joint ventures			59,157	0
Investment in real estate securities			(43,308)	0
Investment in real estate debt securities			(12,514)	0
Proceeds for future development obligations			1,367	0
Funding of development obligations			(926)	(2,726)
Net cash used in investing activities			(56,124)	(291,226)
Cash Flows from Financing Activities:
Proceeds from notes and bonds payable			176,777	462,178
Principal payments on notes and bonds payable			(73,907)	(74,707)
Payments of deferred financing costs			(2,339)	(10,641)
Payments to redeem common stock			(8,050)	(31,454)
Payments of prepaid other offering costs			(376)	(168)
Distributions paid			(7,229)	(6,948)
Noncontrolling interests contributions			150	769
Distributions to noncontrolling interests			(18)	(80)
Acquisitions of noncontrolling interests			0	(37,986)
Other financing proceeds, net			0	693
Net cash provided by financing activities			85,008	301,656
Effect of exchange rate changes on cash, cash equivalents and restricted cash			514	3,711
Net increase in cash, cash equivalents and restricted cash			49,123	34,167
Cash, cash equivalents and restricted cash, beginning of period	113,573	63,032	113,573	63,032	64,450	$ 28,865
Cash, cash equivalents and restricted cash, end of period	$ 113,573	$ 63,032	$ 113,573	$ 63,032	$ 64,450

ORGANIZATION

ORGANIZATION	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
ORGANIZATION	ORGANIZATION KBS Strategic Opportunity REIT, Inc. (the “Company”) was formed on October 8, 2008 as a Maryland corporation and elected to be taxed as a real estate investment trust (“REIT”) beginning with the taxable year ended December 31, 2010. The Company conducts its business primarily through KBS Strategic Opportunity (BVI) Holdings, Ltd. (“KBS Strategic Opportunity BVI”), a private company limited by shares according to the British Virgin Islands Business Companies Act, 2004, which was incorporated on December 18, 2015 and is authorized to issue a maximum of 50,000 common shares with no par value. Upon incorporation, KBS Strategic Opportunity BVI issued one certificate containing 10,000 common shares with no par value to KBS Strategic Opportunity Limited Partnership (the “Operating Partnership”), a Delaware limited partnership formed on December 10, 2008. The Company is the sole general partner of, and owns a 0.1% partnership interest in the Operating Partnership. KBS Strategic Opportunity Holdings LLC (“REIT Holdings”), a Delaware limited liability company formed on December 9, 2008, owns the remaining 99.9% interest in the Operating Partnership and is its sole limited partner. The Company is the sole member and manager of REIT Holdings. Subject to certain restrictions and limitations, the business of the Company is externally managed by KBS Capital Advisors LLC (the “Advisor”), an affiliate of the Company, pursuant to an advisory agreement the Company renewed with the Advisor on October 8, 2017 (the “Advisory Agreement”). The Advisor conducts the Company’s operations and manages its portfolio of real estate, real estate-related debt securities and other real estate-related investments. The Advisor owns 20,000 shares of the Company’s common stock. On January 8, 2009, the Company filed a registration statement on Form S-11 with the Securities and Exchange Commission (the “SEC”) to offer a minimum of 250,000 shares and a maximum of 140,000,000 shares of common stock for sale to the public (the “Offering”), of which 100,000,000 shares were registered in a primary offering and 40,000,000 shares were registered to be sold under the Company’s dividend reinvestment plan. The SEC declared the Company’s registration statement effective on November 20, 2009. The Company ceased offering shares of common stock in its primary offering on November 14, 2012 and continues to offer shares under its dividend reinvestment plan. The Company sold 56,584,976 shares of common stock in its primary offering for gross offering proceeds of $561.7 million . As of September 30, 2017 , the Company had sold 6,620,362 shares of common stock under its dividend reinvestment plan for gross offering proceeds of $74.0 million . Also, as of September 30, 2017 , the Company had redeemed 6,705,949 shares for $85.0 million . Additionally, on December 29, 2011 and October 23, 2012, the Company issued 220,994 shares and 55,249 shares of common stock, respectively, for $2.0 million and $0.5 million , respectively, in private transactions exempt from the registration requirements pursuant to Section 4(2) of the Securities Act of 1933. On March 2, 2016, KBS Strategic Opportunity BVI filed a final prospectus with the Israel Securities Authority for a proposed offering of up to 1,000,000,000 Israeli new Shekels of Series A debentures (the “Debentures”) at an annual interest rate not to exceed 4.25% . On March 1, 2016, KBS Strategic Opportunity BVI commenced the institutional tender of the Debentures and accepted application for 842.5 million Israeli new Shekels. On March 7, 2016, KBS Strategic Opportunity BVI commenced the public tender of the Debentures and accepted 127.7 million Israeli new Shekels. In the aggregate, KBS Strategic Opportunity BVI accepted 970.2 million Israeli new Shekels (approximately $249.2 million as of March 8, 2016) in both the institutional and public tenders at an annual interest rate of 4.25% . KBS Strategic Opportunity BVI issued the Debentures on March 8, 2016. The terms of the Debentures require principal installment payments equal to 20% of the face value of the Debentures on March 1st of each year from 2019 to 2023. In connection with the above-referenced offering, on March 8, 2016, the Operating Partnership assigned to KBS Strategic Opportunity BVI all of its interests in the subsidiaries through which the Company indirectly owns all of its real estate and real estate-related investments. The Operating Partnership owns all of the issued and outstanding equity of KBS Strategic Opportunity BVI. As a result of these transactions, the Company now holds all of its real estate and real estate-related investments indirectly through KBS Strategic Opportunity BVI. As of September 30, 2017 , the Company consolidated 20 real estate investments comprised of 11 office properties, one office campus consisting of nine office buildings, one office portfolio consisting of four office buildings and 25 acres of undeveloped land, one office portfolio consisting of three office properties, one office/flex/industrial portfolio consisting of 21 buildings, one retail property, two apartment properties, two investments in undeveloped land with approximately 1,100 developable acres, and owned three investments in unconsolidated joint ventures, an investment in real estate debt securities and an investment in real estate equity securities.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES There have been no significant changes to the Company’s accounting policies since it filed its audited financial statements in its Annual Report on Form 10-K for the year ended December 31, 2016 , except for the adoption of ASU No. 2017-01 on January 1, 2017 and the addition of an accounting policy with respect to real estate equity securities. For further information about the Company’s accounting policies, refer to the Company’s consolidated financial statements and notes thereto for the year ended December 31, 2016 included in the Company’s Annual Report on Form 10-K filed with the SEC. Principles of Consolidation and Basis of Presentation The accompanying unaudited consolidated financial statements and condensed notes thereto have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information as contained within the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) and the rules and regulations of the SEC, including the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, the unaudited consolidated financial statements do not include all of the information and footnotes required by GAAP for audited financial statements. In the opinion of management, the financial statements for the unaudited interim periods presented include all adjustments, which are of a normal and recurring nature, necessary for a fair and consistent presentation of the results for such periods. Operating results for the three and nine months ended September 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017 . The consolidated financial statements include the accounts of the Company, REIT Holdings, the Operating Partnership, KBS Strategic Opportunity BVI and their direct and indirect wholly owned subsidiaries, and joint ventures in which the Company has a controlling interest. All significant intercompany balances and transactions are eliminated in consolidation. Use of Estimates The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could materially differ from those estimates. Real Estate Equity Securities The Company determines the appropriate classification for real estate equity securities at acquisition (on the trade date) and reevaluates such designation as of each balance sheet date. As of September 30, 2017 , the Company classified its investment in real estate equity securities as available-for-sale as the Company intends to hold the securities for the purpose of collecting dividend income and for longer term price appreciation. These investments are carried at their estimated fair value based on quoted market prices for the security. Transaction costs that are directly attributable to the acquisition of real estate equity securities are capitalized to its cost basis. Unrealized gains and losses are reported in accumulated other comprehensive income (loss). Upon the sale of a security, the previously recognized unrealized gain (loss) would be reversed out of accumulated other comprehensive income (loss) and the actual realized gain (loss) recognized in earnings. Dividend income is recognized on an accrual basis based on eligible shares as of the ex-dividend date. Any non-temporary decline in the market value of an available-for-sale real estate equity security below cost results in a reduction in the carrying amount to fair value. The impairment is charged to earnings and a new cost basis for the real estate security is established. When a real estate equity security is impaired, the Company considers whether it has the ability and intent to hold the investment for a time sufficient to allow for any anticipated recovery in market value and considers whether evidence indicating the cost of the investment being recoverable outweighs evidence to the contrary. Evidence considered in this assessment includes the reasons for the impairment, the severity and duration of the impairment, changes in value subsequent to period end and forecasted performance of the investee. Reclassifications Certain amounts in the Company’s prior period consolidated financial statements have been reclassified to conform to the current period presentation. These reclassifications have not changed the results of operations of the prior period. During the year ended December 31, 2016, the Company elected to early adopt ASU No. 2016-18 (as defined below). As a result, the Company no longer presents transfers between cash and restricted cash in the consolidated statements of cash flows. Instead, restricted cash is included with cash and cash equivalents when reconciling the beginning of period and end of period total amounts shown on the consolidated statements of cash flows. During the nine months ended September 30, 2017 , the Company disposed of one office property. As a result, certain assets and liabilities were reclassified to held for sale on the consolidated balance sheets for all periods presented. Redeemable Common Stock On December 8, 2016, the Company adopted a tenth amended and restated share redemption program (the “Tenth Amended Share Redemption Program”) that may enable stockholders to sell their shares to the Company in limited circumstances. Pursuant to the Tenth Amended Share Redemption Program, except for redemptions made upon a stockholder’s death, “qualifying disability” or “determination of incompetence,” the price at which we will redeem shares is 95% of our most recent estimated value per share as of the applicable redemption date. The Tenth Amended Share Redemption Program was effective on December 30, 2016. Pursuant to the share redemption program there are several limitations on the Company’s ability to redeem shares: • Unless the shares are being redeemed in connection with a stockholder’s death, “qualifying disability” or “determination of incompetence” (each as defined under the share redemption program), the Company may not redeem shares until the stockholder has held the shares for one year. • The Company may not redeem more than $3.0 million of shares in a given quarter (excluding shares redeemed in connection with a stockholder’s death, “qualifying disability” or “determination of incompetence”). To the extent that the Company redeems less than $3.0 million of shares (excluding shares redeemed in connection with a stockholder’s death, “qualifying disability” or “determination of incompetence”) in a given fiscal quarter, any remaining excess capacity to redeem shares in such fiscal quarter will be added to the Company’s capacity to otherwise redeem shares (excluding shares redeemed in connection with a stockholder’s death, “qualifying disability” or “determination of incompetence”) during succeeding fiscal quarters. The last $1.0 million of net proceeds from the dividend reinvestment plan during the prior year is reserved exclusively for shares redeemed in connection with a stockholder’s death, “qualifying disability,” or “determination of incompetence.” The share redemption plan also provides that, to the extent that in the last month of any calendar year the amount of redemption requests in connection with a stockholder’s death, “qualifying disability or “determination of incompetence” is less than the $1.0 million reserved for such redemptions under the share redemption plan, any excess funds may be used to redeem shares not requested in connection with a stockholder’s death, “qualifying disability or “determination of incompetence” during such month. The Company may increase or decrease this limit upon ten business days’ notice to stockholders. The Company’s board of directors may approve an increase in this limit to the extent that the Company has received proceeds from asset sales or the refinancing of debt or for any other reason deemed appropriate by the board of directors. • During any calendar year, the Company may redeem no more than 5% of the weighted-average number of shares outstanding during the prior calendar year. • The Company has no obligation to redeem shares if the redemption would violate the restrictions on distributions under Maryland law, which prohibits distributions that would cause a corporation to fail to meet statutory tests of solvency. The Company’s board of directors may amend, suspend or terminate the share redemption program with ten business days’ notice to its stockholders. On September 14, 2017 , the Company commenced a self-tender offer (the “SOR Offer”) for up to 3,553,660 shares of common stock at a price of $14.07 per share, or approximately $50.0 million of shares. On October 18, 2017 , the Company increased the number of shares accepted for payment in the SOR Offer by up to 1,135,912 shares at a price of $14.07 per share, or approximately $16.0 million of shares. On October 23, 2017 , the Company accepted for purchase 4,688,671 shares for an aggregate cost of $66.0 million , excluding fees and expenses related to the SOR Offer. Because of the SOR Offer, the Tenth Amended Share Redemption Program was suspended from September 29, 2017 through October 31, 2017 , meaning no redemptions were made in September or October (including those requested following a stockholder’s death, “qualifying disability” or “determination of incompetence”). The Company cancelled all outstanding redemption requests under the SRP as of the commencement of the SOR Offer and was not accepting any redemption requests under the SRP during the term of the SOR Offer. The Company records amounts that are redeemable under the share redemption program and the SOR Offer as redeemable common stock in its consolidated balance sheets because the shares are redeemable at the option of the holder to the extent there is sufficient capacity under the share redemption program and therefore their redemption is outside the control of the Company. However, because the amounts that can be redeemed will be determinable and only contingent on an event that is likely to occur (e.g., the passage of time), the Company presents the net proceeds from the current year and prior year DRP, net of current year redemptions, as redeemable common stock in its consolidated balance sheets. The Company classifies as liabilities financial instruments that represent a mandatory obligation of the Company to redeem shares. The Company’s redeemable common shares are contingently redeemable at the option of the holder. When the Company determines it has a mandatory obligation to repurchase shares under the share redemption program, it will reclassify such obligations from temporary equity to a liability based upon their respective settlement values. The Company limits the dollar value of shares that may be redeemed under the program as described above. The Company recorded $11.4 million of other liabilities on the Company’s balance sheet as of September 30, 2017 related to shares submitted for tender under the SOR Offer as of September 30, 2017 . The Company recorded $12.6 million of other liabilities on the Company’s balance sheet as of December 31, 2016 related to unfulfilled redemption requests received in good order under the share redemption program as of December 31, 2016 . As of September 30, 2017 , the Company recorded $52.0 million of redeemable common stock consisting of (i) $38.6 million of the amount available to tender related to the SOR Offer (excludes shares already submitted for tender as of September 30, 2017 ), (ii) $4.7 million available for all redemptions in the remainder of 2017, including shares that are redeemed in connection with a stockholders’ death, “qualifying disability” or “determination of incompetence” based on the amount of net proceeds raised from the sale of shares under the dividend reinvestment plan during 2016 and (iii) $8.7 million available for all redemptions in 2018, including shares that are redeemed in connection with a stockholders’ death, “qualifying disability” or “determination of incompetence” based on the amount of net proceeds raised from the sale of shares under the dividend reinvestment plan during 2017. Segments The Company has invested in non-performing loans, opportunistic real estate and other real estate-related assets. In general, the Company intends to hold its investments in non-performing loans, opportunistic real estate and other real estate‑related assets for capital appreciation. Traditional performance metrics of non-performing loans, opportunistic real estate and other real estate-related assets may not be meaningful as these investments are generally non-stabilized and do not provide a consistent stream of interest income or rental revenue. These investments exhibit similar long-term financial performance and have similar economic characteristics. These investments typically involve a higher degree of risk and do not provide a constant stream of ongoing cash flows. As a result, the Company’s management views non-performing loans, opportunistic real estate and other real estate-related assets as similar investments. Substantially all of its revenue and net income (loss) is from non-performing loans, opportunistic real estate and other real estate-related assets, and therefore, the Company currently aggregates its operating segments into one reportable business segment. Per Share Data Basic net income (loss) per share of common stock is calculated by dividing net income (loss) attributable to common stockholders by the weighted-average number of shares of common stock issued and outstanding during such period. Diluted net income (loss) per share of common stock equals basic net income (loss) per share of common stock as there were no potentially dilutive securities outstanding during the three and nine months ended September 30, 2017 and 2016 . Distributions declared per share were $0.09452055 and $0.28047945 during the three and nine months ended September 30, 2017 , respectively, and $0.09426230 and $0.28073770 during the three and nine months ended September 30, 2016 , respectively. Square Footage, Occupancy and Other Measures Any references to square footage, occupancy or annualized base rent are unaudited and outside the scope of the Company’s independent registered public accounting firm’s review of the Company’s financial statements in accordance with the standards of the United States Public Company Accounting Oversight Board. Recently Issued Accounting Standards Updates In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) (“ASU No. 2014-09”). ASU No. 2014-09 requires an entity to recognize the revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. ASU No. 2014-09 supersedes the revenue requirements in Revenue Recognition (Topic 605) and most industry-specific guidance throughout the Industry Topics of the Codification. ASU No. 2014-09 does not apply to lease contracts within the scope of Leases (Topic 840). ASU No. 2014-09 was to be effective for fiscal years, and interim periods within those years, beginning after December 15, 2016, and is to be applied retrospectively, with early application not permitted. In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date (“ASU No. 2015-14”), which defers the effective date of ASU No. 2014-09 by one year. Early adoption is permitted but not before the original effective date. The primary source of revenue for the Company is generated through leasing arrangements, which are excluded from this standard. The Company’s revenues that may be impacted by this standard primarily include other operating income, sales of real estate, including land parcels and operating properties, and other ancillary income earned at its properties. In 2016, other operating income and other ancillary income were approximately 5% of consolidated revenue. The Company is in the process of evaluating how this standard will impact sales of real estate. The Company continues to evaluate the impact that the standard will have on its consolidated financial statements. The Company expects to adopt the standard using the modified retrospective approach, which requires a cumulative effect adjustment as of the date of the adoption. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities (“ASU No. 2016-01”). The amendments in ASU No. 2016-01 address certain aspects of recognition, measurement, presentation and disclosure of financial instruments. ASU No. 2016-01 primarily affects accounting for equity investments and financial liabilities where the fair value option has been elected. ASU No. 2016-01 supersedes the guidance to classify equity securities with readily determinable fair values into different categories (that is, trading or available-for-sale) and requires equity securities (including other ownership interests, such as partnerships, unincorporated joint ventures, and limited liability companies) to be measured at fair value with changes in the fair value recognized through net income. ASU No. 2016-01 also requires entities to present financial assets and financial liabilities separately, grouped by measurement category and form of financial asset in the balance sheet or in the accompanying notes to the financial statements. ASU No. 2016-01 is effective for annual periods beginning after December 15, 2017, including interim periods within those fiscal years. Early application of certain provisions of the standard is permitted for financial statements that have not been previously issued. Upon adoption, the Company will be required to record net unrealized gain or loss on real estate equity securities in earnings and record a cumulative effect adjustment to the balance sheet. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) (“ASU No. 2016-02”). The amendments in ASU No. 2016-02 change the existing accounting standards for lease accounting, including requiring lessees to recognize most leases on their balance sheets and making targeted changes to lessor accounting. ASU No. 2016-02 is effective for annual periods beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption of ASU No. 2016-02 is permitted. The new leases standard requires a modified retrospective transition approach for all leases existing at, or entered into after, the date of initial application, with an option to use certain transition relief. The Company is currently evaluating the impact of adopting the new leases standard on its consolidated financial statements. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses of Financial Instruments (“ASU No. 2016-13”). ASU No. 2016-13 affects entities holding financial assets and net investments in leases that are not accounted for at fair value through net income. The amendments in ASU No. 2016-13 require a financial asset (or a group of financial assets) measured at amortized cost basis to be presented at the net amount expected to be collected. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of the financial asset(s) to present the net carrying value at the amount expected to be collected on the financial asset. ASU No. 2016-13 also amends the impairment model for available-for-sale securities. An entity will recognize an allowance for credit losses on available-for-sale debt securities as a contra-account to the amortized cost basis rather than as a direct reduction of the amortized cost basis of the investment, as is currently required. ASU No. 2016-13 also requires new disclosures. For financial assets measured at amortized cost, an entity will be required to disclose information about how it developed its allowance for credit losses, including changes in the factors that influenced management’s estimate of expected credit losses and the reasons for those changes. For financing receivables and net investments in leases measured at amortized cost, an entity will be required to further disaggregate the information it currently discloses about the credit quality of these assets by year of the asset’s origination for as many as five annual periods. For available-for-sale securities, an entity will be required to provide a roll-forward of the allowance for credit losses and an aging analysis for securities that are past due. ASU No. 2016-13 is effective for annual periods beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company is still evaluating the impact of adopting ASU No. 2016-13 on its financial statements. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (“ASU No. 2016-15”). ASU No. 2016-15 is intended to reduce diversity in practice in how certain transactions are classified in the statement of cash flows. The amendments in ASU No. 2016-15 provide guidance on eight specific cash flow issues, including the following that are or may be relevant to the Company: (a) Cash payments for debt prepayment or debt extinguishment costs should be classified as cash outflows for financing activities; (b) Cash payments relating to contingent consideration made soon after an acquisition’s consummation date (i.e., approximately three months or less) should be classified as cash outflows for investing activities. Payments made thereafter should be classified as cash outflows for financing activities up to the amount of the original contingent consideration liability. Payments made in excess of the amount of the original contingent consideration liability should be classified as cash outflows for operating activities; (c) Cash payments received from the settlement of insurance claims should be classified on the basis of the nature of the loss (or each component loss, if an entity receives a lump-sum settlement); and (d) Relating to distributions received from equity method investments, ASU No. 2016-15 provides an accounting policy election for classifying distributions received from equity method investments. Such amounts can be classified using a (1) cumulative earnings approach, or (2) nature of distribution approach. Under the cumulative earnings approach, an investor would compare the distributions received to its cumulative equity method earnings since inception. Any distributions received up to the amount of cumulative equity earnings would be considered a return on investment and classified in operating activities. Any excess distributions would be considered a return of investment and classified in investing activities. Alternatively, an investor can choose to classify the distributions based on the nature of activities of the investee that generated the distribution. If the necessary information is subsequently not available for an investee to determine the nature of the activities, the entity should use the cumulative earnings approach for that investee and report a change in accounting principle on a retrospective basis; (e) In the absence of specific guidance, an entity should classify each separately identifiable cash source and use on the basis of the nature of the underlying cash flows. For cash flows with aspects of more than one class that cannot be separated, the classification should be based on the activity that is likely to be the predominant source or use of cash flow. ASU No. 2016-15 is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. The Company is still evaluating the impact of adopting ASU No. 2016-15 on its financial statements, but does not expect the adoption of ASU No. 2016-15 to have a material impact on its financial statements. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (“ASU No. 2016-18”). ASU No. 2016-18 requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, restricted cash and restricted cash equivalents. Therefore, amounts generally described as restricted cash should be included with cash and cash equivalents when reconciling the beginning of period and end of period total amounts shown on the statement of cash flows. ASU No. 2016-18 is effective for annual periods beginning after December 15, 2017, including interim periods within those fiscal years. The Company elected to early adopt ASU No. 2016-18 for the reporting period ending December 31, 2016 and was applied retrospectively. As a result of adoption of ASU No. 2016-18, the Company no longer presents the changes within restricted cash in the consolidated statements of cash flows. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business (“ASU No. 2017-01”) to add guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. ASU No. 2017-01 provides a screen to determine when an integrated set of assets and activities (collectively referred to as a “set”) is not a business. The screen requires that, when substantially all of the fair value of the gross assets acquired (or disposed of) is concentrated in a single identifiable asset or a group of similar identifiable assets, the set is not a business. If the screen is not met, ASU No. 2017-01 (1) requires that to be considered a business, a set must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output and (2) removes the evaluation of whether a market participant could replace missing elements. ASU No. 2017-01 provides a framework to assist entities in evaluating whether both an input and a substantive process are present. The framework includes two sets of criteria to consider that depend on whether a set has outputs. Although outputs are not required for a set to be a business, outputs generally are a key element of a business; therefore, the FASB has developed more stringent criteria for sets without outputs. ASU No. 2017-01 is effective for annual periods beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted. The amendments can be applied to transactions occurring before the guidance was issued (January 5, 2017) as long as the applicable financial statements have not been issued. The Company elected to early adopt ASU No. 2017-01 for the reporting period beginning January 1, 2017. As a result of the adoption of ASU No. 2017-01, the Company’s acquisitions of investment properties beginning January 1, 2017 could qualify as asset acquisitions (as opposed to business combinations). Transaction costs associated with asset acquisitions are capitalized, while transaction costs associated with business combinations will continue to be expensed as incurred.

REAL ESTATE HELD FOR INVESTMENT

REAL ESTATE HELD FOR INVESTMENT	9 Months Ended
	Sep. 30, 2017
Real Estate [Abstract]
REAL ESTATE FOR INVESTMENT	REAL ESTATE HELD FOR INVESTMENT As of September 30, 2017 , the Company owned 11 office properties, one office campus consisting of nine office buildings, one office portfolio consisting of four office buildings and 25 acres of undeveloped land, one office portfolio consisting of three office properties, one office/flex/industrial portfolio consisting of 21 buildings, one retail property encompassing, in the aggregate, approximately 6.0 million rentable square feet. As of September 30, 2017 , these properties were 83% occupied. In addition, the Company owned two apartment properties, containing 383 units and encompassing approximately 0.3 million rentable square feet, which were 97% occupied. The Company also owned two investments in undeveloped land with approximately 1,100 developable acres. The following table summarizes the Company’s real estate held for investment as of September 30, 2017 and December 31, 2016 , respectively (in thousands): September 30, 2017 December 31, 2016 Land $ 280,254 $ 312,623 Buildings and improvements 847,773 814,347 Tenant origination and absorption costs 49,210 46,557 Total real estate, cost 1,177,237 1,173,527 Accumulated depreciation and amortization (131,566 ) (113,429 ) Total real estate, net $ 1,045,671 $ 1,060,098 The following table provides summary information regarding the Company’s real estate held for investment as of September 30, 2017 (in thousands): Property Date City State Property Type Land Building Tenant Origination and Absorption Total Accumulated Depreciation and Amortization Total Ownership % Northridge Center I & II (1) 03/25/2011 Atlanta GA Office $ 2,234 $ 6,914 $ — $ 9,148 $ (2,584 ) $ 6,564 100.0 % Iron Point Business Park (1) 06/21/2011 Folsom CA Office 2,671 19,547 — 22,218 (5,648 ) 16,570 100.0 % Richardson Portfolio: Palisades Central I 11/23/2011 Richardson TX Office 1,037 10,278 — 11,315 (2,202 ) 9,113 90.0 % Palisades Central II 11/23/2011 Richardson TX Office 810 17,540 — 18,350 (4,111 ) 14,239 90.0 % Greenway I 11/23/2011 Richardson TX Office 561 2,309 — 2,870 (791 ) 2,079 90.0 % Greenway III 11/23/2011 Richardson TX Office 702 3,802 559 5,063 (1,736 ) 3,327 90.0 % Undeveloped Land 11/23/2011 Richardson TX Undeveloped Land 3,134 — — 3,134 — 3,134 90.0 % Total Richardson Portfolio 6,244 33,929 559 40,732 (8,840 ) 31,892 Park Highlands (2) 12/30/2011 North Las Vegas NV Undeveloped Land 33,594 — — 33,594 — 33,594 (2) Bellevue Technology (1) 07/31/2012 Bellevue WA Office 25,506 56,409 1,767 83,682 (10,418 ) 73,264 100.0 % Powers Ferry Landing (1) 09/24/2012 Atlanta GA Office 1,643 7,642 — 9,285 (2,505 ) 6,780 100.0 % 1800 West Loop (1) 12/04/2012 Houston TX Office 8,360 60,481 4,176 73,017 (14,100 ) 58,917 100.0 % West Loop I & II (1) 12/07/2012 Houston TX Office 7,300 32,867 1,662 41,829 (7,024 ) 34,805 100.0 % Burbank Collection 12/12/2012 Burbank CA Retail 4,175 12,551 725 17,451 (2,198 ) 15,253 90.0 % Austin Suburban Portfolio (3) 03/28/2013 Austin TX Office 8,288 69,478 836 78,602 (10,851 ) 67,751 100.0 % Westmoor Center (1) 06/12/2013 Westminster CO Office 10,058 73,283 5,083 88,424 (15,050 ) 73,374 100.0 % Central Building 07/10/2013 Seattle WA Office 7,015 27,055 1,428 35,498 (4,701 ) 30,797 100.0 % 1180 Raymond 08/20/2013 Newark NJ Apartment 8,292 38,049 — 46,341 (4,938 ) 41,403 100.0 % Park Highlands II 12/10/2013 North Las Vegas NV Undeveloped Land 24,692 — — 24,692 — 24,692 100.0 % Maitland Promenade II (1) 12/18/2013 Orlando FL Office 3,434 25,033 3,313 31,780 (5,492 ) 26,288 100.0 % Plaza Buildings (1) 01/14/2014 Bellevue WA Office 53,040 139,383 7,190 199,613 (23,723 ) 175,890 100.0 % 424 Bedford 01/31/2014 Brooklyn NY Apartment 8,860 25,615 — 34,475 (2,616 ) 31,859 90.0 % Richardson Land II 09/04/2014 Richardson TX Undeveloped Land 3,418 — — 3,418 — 3,418 90.0 % Westpark Portfolio 05/10/2016 Redmond WA Office/Flex/Industrial 36,085 88,125 7,663 131,873 (7,871 ) 124,002 100.0 % Crown Pointe 02/14/2017 Dunwoody GA Office 22,590 57,815 5,855 86,260 (2,807 ) 83,453 100.0 % 125 John Carpenter 09/15/2017 Irving TX Office 2,755 73,597 8,953 85,305 (200 ) 85,105 100.0 % $ 280,254 $ 847,773 $ 49,210 $ 1,177,237 $ (131,566 ) $ 1,045,671 _____________________ (1) On November 8, 2017 , the Company sold this property. See note 15 , “Subsequent Events - Singapore Transaction ” for more information. (2) On September 7, 2016, a subsidiary of the Company that owns a portion of Park Highlands, sold 820 units of 10% Class A non-voting preferred membership units for $0.8 million to accredited investors. The amount of the Class A non-voting preferred membership units raised, net of offering costs, is included in other liabilities on the accompanying consolidated balance sheets. (3) On November 8, 2017 , the Company sold two of the three office properties, Westech 360 and Great Hills Plaza. See note 15 , “Subsequent Events - Singapore Transaction ” for more information. Operating Leases Certain of the Company’s real estate properties are leased to tenants under operating leases for which the terms and expirations vary. As of September 30, 2017 , the leases, excluding options to extend and apartment leases, which have terms that are generally one year or less, had remaining terms of up to 14.7 years with a weighted-average remaining term of 3.8 years. Some of the leases have provisions to extend the lease agreements, options for early termination after paying a specified penalty, rights of first refusal to purchase the property at competitive market rates, and other terms and conditions as negotiated. The Company retains substantially all of the risks and benefits of ownership of the real estate assets leased to tenants. Generally, upon the execution of a lease, the Company requires a security deposit from tenants in the form of a cash deposit and/or a letter of credit. The amount required as a security deposit varies depending upon the terms of the respective leases and the creditworthiness of the tenant, but generally are not significant amounts. Therefore, exposure to credit risk exists to the extent that a receivable from a tenant exceeds the amount of its security deposit. Security deposits received in cash and assumed in real estate acquisitions or foreclosures related to tenant leases are included in other liabilities in the accompanying consolidated balance sheets and totaled $7.3 million and $7.2 million as of September 30, 2017 and December 31, 2016 , respectively. During the nine months ended September 30, 2017 and 2016 , the Company recognized deferred rent from tenants of $1.7 million and $2.0 million , respectively, net of lease incentive amortization. As of September 30, 2017 and December 31, 2016 , the cumulative deferred rent receivable balance, including unamortized lease incentive receivables, was $27.0 million and $26.1 million , respectively, and is included in rents and other receivables on the accompanying balance sheets. The cumulative deferred rent balance included $3.0 million and $3.2 million of unamortized lease incentives as of September 30, 2017 and December 31, 2016 , respectively. The Company records property operating expense reimbursements due from tenants for common area maintenance, real estate taxes, and other recoverable costs in the period the related expenses are incurred. As of September 30, 2017 , the future minimum rental income from the Company’s properties, excluding apartment leases, under non-cancelable operating leases was as follows (in thousands): October 1, 2017 through December 31, 2017 $ 25,468 2018 99,939 2019 87,116 2020 71,983 2021 55,922 Thereafter 137,582 $ 478,010 As of September 30, 2017 , the Company’s commercial real estate properties were leased to approximately 600 tenants over a diverse range of industries and geographic areas. The Company’s highest tenant industry concentrations (greater than 10% of annualized base rent) were as follows: Industry Number of Tenants Annualized Base Rent (1) (in thousands) Percentage of Annualized Base Rent Insurance Carriers & Related Activities 35 $ 11,256 10.6 % Computer System Design & Programming 55 11,246 10.6 % $ 22,502 21.2 % _____________________ (1) Annualized base rent represents annualized contractual base rental income as of September 30, 2017 , adjusted to straight-line any contractual tenant concessions (including free rent), rent increases and rent decreases from the lease’s inception through the balance of the lease term. No other tenant industries accounted for more than 10% of annualized base rent. No material tenant credit issues have been identified at this time. Geographic Concentration Risk As of September 30, 2017 , the Company’s real estate investments in Washington and Texas represented 30.0% and 21.0% , respectively, of the Company’s total assets. As a result, the geographic concentration of the Company’s portfolio makes it particularly susceptible to adverse economic developments in the Washington and Texas real estate markets. Any adverse economic or real estate developments in these markets, such as business layoffs or downsizing, industry slowdowns, relocations of businesses, changing demographics and other factors, or any decrease in demand for office space resulting from the local business climate, could adversely affect the Company’s operating results and its ability to make distributions to stockholders. Recent Real Estate Land Sale On May 1, 2017, the Company sold an aggregate of 102 developable acres of Park Highlands undeveloped land for an aggregate sales price, net of closing credits, of $17.4 million , excluding closing costs. The purchasers are not affiliated with the Company or the Advisor. The Company recognized a gain on sale based on the percentage of completion method due to the Company’s continuing development obligations to the purchasers. The Company recognized a gain on sale of $5.2 million related to the land sale, which is net of deferred profit of $2.6 million . In addition, the Company deferred $1.7 million related to proceeds received from the purchasers and another developer for the value of land that was contributed to a master association which is consolidated by the Company. Recent Sale of Partial Interest of Real Estate On July 6, 2017, KBS SOR Properties, LLC, an indirect wholly owned affiliate of the Company, entered into (i) a Common Unit Purchase and Sale Agreement and Escrow Instructions with Migdal Insurance Company LTD., Migdal-Makefet Pension and Provident Funds LTD. and affiliates (the “Migdal Members”) (the “Purchase and Sale Agreement”), (ii) the Amended and Restated Limited Liability Company Agreement of KBS SOR Acquisition XXIX, LLC (the “Joint Venture Agreement”), (iii) an Investment Agreement with Migdal Members and Willowbrook Asset Management LLC, which is owned by Keith D. Hall and Peter McMillan III, who are principals of the Advisor and directors and officers of the Company (“WBAM”), and (iv) a waiver letter agreement with the Advisor (the “Waiver Agreement”). Pursuant to the Purchase and Sale Agreement, on July 6, 2017, KBS SOR Properties, LLC sold a 45% equity interest in an entity that owns an office building containing 284,751 rentable square feet located on approximately 0.35 acres of land in San Francisco, California (“353 Sacramento”) for approximately $39.1 million (the “353 Sacramento Transaction”) to the Migdal Members, third parties unaffiliated with the Company or the Advisor. The sale resulted in 353 Sacramento being owned by a joint venture (the “353 Sacramento Joint Venture”) in which the Company indirectly owns 55% of the equity interests and the Migdal Members indirectly own 45% in the aggregate of the equity interests. The Company exercises significant influence over the operations, financial policies and decision making with respect to the 353 Sacramento Joint Venture but significant decisions require approval from both members. Accordingly, the Company has accounted for its investment in the 353 Sacramento Joint Venture under the equity method of accounting. Income, losses, contributions and distributions are generally allocated based on the members’ respective equity interests. Therefore, as of July 6, 2017, the Company deconsolidated 353 Sacramento and accounted for this investment as an unconsolidated joint venture under the equity method of accounting. The Company recognized a gain on sale of $1.7 million related to the sale and deconsolidation. See note 12 , “Investment in Unconsolidated Joint Ventures” for a further discussion on the Company’s investment in the 353 Sacramento Joint Venture. Recent Acquisitions Crown Pointe On February 14, 2017, the Company, through an indirect wholly owned subsidiary, acquired an office property consisting of two office buildings containing an aggregate of 499,968 rentable square feet in Dunwoody, Georgia (“Crown Pointe”). The seller is not affiliated with the Company or the Advisor. The purchase price (net of closing credits) of Crown Pointe was $83.1 million plus $1.1 million of capitalized acquisition costs. The Company recorded this acquisition as an asset acquisition and recorded $22.6 million to land, $56.6 million to building and improvements, $6.0 million to tenant origination and absorption costs and $1.0 million to below-market lease liabilities. The intangible assets and liabilities acquired in connection with this acquisition have weighted-average amortization periods as of the date of acquisition of 4.9 years for tenant origination and absorption costs and 4.2 years for below-market lease liabilities. During the three and nine months ended September 30, 2017 , the Company recognized $2.3 million and $6.1 million , respectively, of total revenues and $1.9 million and $4.7 million , respectively, of operating expenses from this property. 125 John Carpenter On September 15, 2017, the Company, through an indirect wholly owned subsidiary, acquired an office property consisting of two office buildings containing an aggregate of 442,039 rentable square feet in Irving, Texas (“125 John Carpenter”). The seller is not affiliated with the Company or the Advisor. The purchase price (net of closing credits) of 125 John Carpenter was $82.8 million plus $0.5 million of capitalized acquisition costs. The Company recorded this acquisition as an asset acquisition and recorded $2.7 million to land, $73.6 million to building and improvements, $9.0 million to tenant origination and absorption costs and $2.1 million to below-market lease liabilities. The intangible assets and liabilities acquired in connection with this acquisition have weighted-average amortization periods as of the date of acquisition of 6.9 years for tenant origination and absorption costs and 5.2 years for below-market lease liabilities. During the three and nine months ended September 30, 2017 , the Company recognized $0.5 million of total revenues and $0.3 million of operating expenses from this property.

TENANT ORIGINATION AND ABSORPTI

TENANT ORIGINATION AND ABSORPTION COSTS, ABOVE-MARKET LEASE ASSETS AND BELOW-MARKET LEASE LIABILITIES	9 Months Ended
	Sep. 30, 2017
Tenant Origination and Absorption Costs, Above-Market Lease Assets and Below-Market Lease Liabilities [Abstract]
TENANT ORIGINATION AND ABSORPTION COSTS, ABOVE-MARKET LEASE ASSETS AND BELOW-MARKET LEASE LIABILITIES	TENANT ORIGINATION AND ABSORPTION COSTS, ABOVE-MARKET LEASE ASSETS AND BELOW-MARKET LEASE LIABILITIES As of September 30, 2017 and December 31, 2016 , the Company’s tenant origination and absorption costs, above-market lease assets and below-market lease liabilities (excluding fully amortized assets and liabilities and accumulated amortization) were as follows (in thousands): Tenant Origination and Absorption Costs Above-Market Lease Assets Below-Market Lease Liabilities September 30, 2017 December 31, 2016 September 30, 2017 December 31, 2016 September 30, 2017 December 31, 2016 Cost $ 49,210 $ 46,557 $ 1,330 $ 1,808 $ (6,015 ) $ (9,189 ) Accumulated Amortization (21,621 ) (22,327 ) (935 ) (1,190 ) 2,264 3,160 Net Amount $ 27,589 $ 24,230 $ 395 $ 618 $ (3,751 ) $ (6,029 ) Increases (decreases) in net income as a result of amortization of the Company’s tenant origination and absorption costs, above-market lease assets and below-market lease liabilities for the three and nine months ended September 30, 2017 and 2016 were as follows (in thousands): Tenant Origination and Absorption Costs Above-Market Lease Assets Below-Market Lease Liabilities For the Three Months Ended For the Three Months Ended For the Three Months Ended 2017 2016 2017 2016 2017 2016 Amortization $ (2,190 ) $ (3,068 ) $ (62 ) $ (119 ) $ 278 $ 1,045 Tenant Origination and Above-Market Below-Market For the Nine Months Ended For the Nine Months Ended For the Nine Months Ended 2017 2016 2017 2016 2017 2016 Amortization $ (8,268 ) $ (7,765 ) $ (229 ) $ (359 ) $ 2,482 $ 1,734 Additionally, as of September 30, 2017 and December 31, 2016 , the Company had recorded tax abatement intangible assets, net of amortization, which are included in prepaid expenses and other assets in the accompanying balance sheets, of $5.6 million and $6.3 million , respectively. During the three and nine months ended September 30, 2017 , the Company recorded amortization expense of $0.2 million and $0.7 million , respectively, related to tax abatement intangible assets. During the three and nine months ended September 30, 2016 , the Company recorded amortization expense of $0.2 million and $0.7 million , respectively, related to tax abatement intangible assets.

REAL ESTATE EQUITY SECURITIES

REAL ESTATE EQUITY SECURITIES	9 Months Ended
	Sep. 30, 2017
Investments, Debt and Equity Securities [Abstract]
REAL ESTATE EQUITY SECURITIES	REAL ESTATE EQUITY SECURITIES During the nine months ended September 30, 2017 , the Company purchased 3,603,189 shares of common stock of Whitestone REIT (Ticker: WSR) for an aggregate purchase price of $43.3 million , including $0.4 million of acquisition fees paid to the Advisor. The Company's investment in real estate equity securities is classified as available-for-sale as the Company intends to hold the securities for the purpose of collecting dividend income and for longer term price appreciation. These investments are carried at their estimated fair value based on quoted market prices for the security. Transaction costs that are directly attributable to the acquisition of real estate equity securities are capitalized to its cost basis. Unrealized gains and losses are reported in accumulated other comprehensive income (loss). The following summarizes the activity related to real estate equity securities for the nine months ended September 30, 2017 (in thousands): Amortized Cost Basis Unrealized Gains Total Real estate equity securities - December 31, 2016 $ — $ — $ — Purchase of real estate equity securities 42,845 — 42,845 Acquisition fee to affiliate and purchase commission 463 — 463 Unrealized change in market value of real estate equity securities — 3,714 3,714 Real estate equity securities - September 30, 2017 $ 43,308 $ 3,714 $ 47,022 During the three and nine months ended September 30, 2017 , the Company recognized $1.0 million and $1.5 million , respectively, of dividend income from real estate equity securities. REAL ESTATE DEBT SECURITIES As of September 30, 2017 , the Company owned an investment in real estate debt securities. The Company’s investment in real estate debt securities is classified as held to maturity, as the Company has the intent and ability to hold its investment until maturity, and it is not more likely than not that the Company would be required to sell its investment before recovery of the Company’s amortized cost basis. The information for those real estate debt securities as of September 30, 2017 and December 31, 2016 is set forth below (in thousands): Debt Securities Name Dates Acquired Debt Securities Type Outstanding Principal Balance as of September 30, 2017 (1) Book Value as of September 30, 2017 (2) Book Value as of December 31, 2016 (2) Contractual Interest Rate (3) Annualized Effective Interest Rate (3) Maturity Date Battery Point Series B Preferred Units 10/28/2016 / 03/30/2017 / 05/12/2017 Series B Preferred Units $ 17,500 $ 17,642 $ 4,683 9.0 % 11.1 % 10/28/2019 _____________________ (1) Outstanding principal balance as of September 30, 2017 represents principal balance outstanding under the real estate debt securities. (2) Book value of the real estate debt securities represents outstanding principal balance adjusted for unamortized acquisition discounts, origination fees and direct origination and acquisition costs and additional interest accretion. (3) Contractual interest rate is the stated interest rate on the face of the real estate securities. Annualized effective interest rate is calculated as the actual interest income recognized in 2017 , using the interest method, annualized (if applicable) and divided by the average amortized cost basis of the investment. The annualized effective interest rate and contractual interest rate presented are as of September 30, 2017 . The following summarizes the activity related to real estate debt securities for the nine months ended September 30, 2017 (in thousands): Real estate debt securities - December 31, 2016 $ 4,683 Face value of additional real estate debt securities acquired 12,500 Deferred interest receivable and interest accretion 218 Closing costs 3 Accretion of commitment fee, net of closing costs 238 Real estate debt securities - September 30, 2017 $ 17,642 For the three and nine months ended September 30, 2017 , interest income from real estate debt securities consisted of the following (in thousands): Three Months Ended Nine Months Ended September 30, 2017 September 30, 2017 Contractual interest income $ 403 $ 815 Interest accretion 97 218 Accretion of commitment fee, net of closing costs and acquisition fee 11 238 Interest income from real estate debt securities $ 511 $ 1,271

REAL ESTATE DEBT SECURITIES

REAL ESTATE DEBT SECURITIES	9 Months Ended
	Sep. 30, 2017
Investments, Debt and Equity Securities [Abstract]
REAL ESTATE DEBT SECURITIES	REAL ESTATE EQUITY SECURITIES During the nine months ended September 30, 2017 , the Company purchased 3,603,189 shares of common stock of Whitestone REIT (Ticker: WSR) for an aggregate purchase price of $43.3 million , including $0.4 million of acquisition fees paid to the Advisor. The Company's investment in real estate equity securities is classified as available-for-sale as the Company intends to hold the securities for the purpose of collecting dividend income and for longer term price appreciation. These investments are carried at their estimated fair value based on quoted market prices for the security. Transaction costs that are directly attributable to the acquisition of real estate equity securities are capitalized to its cost basis. Unrealized gains and losses are reported in accumulated other comprehensive income (loss). The following summarizes the activity related to real estate equity securities for the nine months ended September 30, 2017 (in thousands): Amortized Cost Basis Unrealized Gains Total Real estate equity securities - December 31, 2016 $ — $ — $ — Purchase of real estate equity securities 42,845 — 42,845 Acquisition fee to affiliate and purchase commission 463 — 463 Unrealized change in market value of real estate equity securities — 3,714 3,714 Real estate equity securities - September 30, 2017 $ 43,308 $ 3,714 $ 47,022 During the three and nine months ended September 30, 2017 , the Company recognized $1.0 million and $1.5 million , respectively, of dividend income from real estate equity securities. REAL ESTATE DEBT SECURITIES As of September 30, 2017 , the Company owned an investment in real estate debt securities. The Company’s investment in real estate debt securities is classified as held to maturity, as the Company has the intent and ability to hold its investment until maturity, and it is not more likely than not that the Company would be required to sell its investment before recovery of the Company’s amortized cost basis. The information for those real estate debt securities as of September 30, 2017 and December 31, 2016 is set forth below (in thousands): Debt Securities Name Dates Acquired Debt Securities Type Outstanding Principal Balance as of September 30, 2017 (1) Book Value as of September 30, 2017 (2) Book Value as of December 31, 2016 (2) Contractual Interest Rate (3) Annualized Effective Interest Rate (3) Maturity Date Battery Point Series B Preferred Units 10/28/2016 / 03/30/2017 / 05/12/2017 Series B Preferred Units $ 17,500 $ 17,642 $ 4,683 9.0 % 11.1 % 10/28/2019 _____________________ (1) Outstanding principal balance as of September 30, 2017 represents principal balance outstanding under the real estate debt securities. (2) Book value of the real estate debt securities represents outstanding principal balance adjusted for unamortized acquisition discounts, origination fees and direct origination and acquisition costs and additional interest accretion. (3) Contractual interest rate is the stated interest rate on the face of the real estate securities. Annualized effective interest rate is calculated as the actual interest income recognized in 2017 , using the interest method, annualized (if applicable) and divided by the average amortized cost basis of the investment. The annualized effective interest rate and contractual interest rate presented are as of September 30, 2017 . The following summarizes the activity related to real estate debt securities for the nine months ended September 30, 2017 (in thousands): Real estate debt securities - December 31, 2016 $ 4,683 Face value of additional real estate debt securities acquired 12,500 Deferred interest receivable and interest accretion 218 Closing costs 3 Accretion of commitment fee, net of closing costs 238 Real estate debt securities - September 30, 2017 $ 17,642 For the three and nine months ended September 30, 2017 , interest income from real estate debt securities consisted of the following (in thousands): Three Months Ended Nine Months Ended September 30, 2017 September 30, 2017 Contractual interest income $ 403 $ 815 Interest accretion 97 218 Accretion of commitment fee, net of closing costs and acquisition fee 11 238 Interest income from real estate debt securities $ 511 $ 1,271

REAL ESTATE SALES

REAL ESTATE SALES	9 Months Ended
	Sep. 30, 2017
Discontinued Operations and Disposal Groups [Abstract]
REAL ESTATE SALES	REAL ESTATE SALES During the three and nine months ended September 30, 2017 , the Company disposed of one office property. During the year ended December 31, 2016 , the Company did not dispose of any real estate properties. On July 11, 2013, the Company, through an indirect wholly owned subsidiary, acquired an office building containing 179,872 rentable square feet located in Boston, Massachusetts (“50 Congress Street”). On May 15, 2017, the Company sold 50 Congress Street to a purchaser unaffiliated with the Company or the Advisor for $79.0 million , or $78.8 million net of concessions and credits. The carrying value of 50 Congress Street as of the disposition date was $47.7 million , which was net of $5.9 million of accumulated depreciation and amortization. The Company recognized a gain on sale of $29.4 million related to the disposition of 50 Congress Street. The following summary presents the major components of assets and liabilities related to real estate held for sale as of September 30, 2017 and December 31, 2016 (in thousands): September 30, 2017 December 31, 2016 Assets related to real estate held for sale Real estate, cost $ — $ 53,680 Accumulated depreciation and amortization — (6,747 ) Real estate, net — 46,933 Other assets — 1,488 Total assets related to real estate held for sale $ — $ 48,421 Liabilities related to real estate held for sale Notes payable, net — 31,450 Other liabilities — 522 Total liabilities related to real estate held for sale $ — $ 31,972 The operations of this property and gain on sale are included in continuing operations on the accompanying statements of operations. The following table summarizes certain revenue and expenses related to this property for the three and nine months ended September 30, 2017 and 2016 (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 Revenues Rental income $ — $ 1,481 $ 2,287 $ 4,462 Tenant reimbursements and other operating income — 151 98 323 Total revenues $ — $ 1,632 $ 2,385 $ 4,785 Expenses Operating, maintenance, and management $ — $ 400 $ 714 $ 1,244 Real estate taxes and insurance — 269 475 864 Asset management fees to affiliate — 102 150 303 Depreciation and amortization — 593 604 1,808 Interest expense — 209 396 599 Total expenses $ — $ 1,573 $ 2,339 $ 4,818

NOTES AND BOND PAYABLE

NOTES AND BOND PAYABLE	9 Months Ended
	Sep. 30, 2017
Notes and Bonds Payable [Abstract]
NOTES AND BOND PAYABLE	NOTES AND BONDS PAYABLE As of September 30, 2017 and December 31, 2016 , the Company’s notes and bonds payable, including notes payable related to real estate held for sale, consisted of the following (dollars in thousands): Book Value as of September 30, 2017 Book Value as of December 31, 2016 Contractual Interest Rate as of September 30, 2017 (1) Effective Interest Rate at September 30, 2017 (1) Payment Type Maturity (2) Richardson Portfolio Mortgage Loan $ 37,036 $ 40,594 One-Month LIBOR + 2.10% 3.34% Principal & Interest 05/01/2018 Bellevue Technology Center Mortgage Loan (3) 58,860 59,400 One-Month LIBOR + 2.25% 3.49% Principal & Interest 03/01/2019 Portfolio Revolving Loan Facility (4) 44,600 11,799 One-Month LIBOR + 2.75% 3.99% Principal & Interest 05/01/2019 Portfolio Mortgage Loan (5) 107,905 106,479 One-Month LIBOR + 2.25% 3.49% Principal & Interest 07/01/2018 Burbank Collection Mortgage Loan 9,591 9,812 One-Month LIBOR + 2.35% 3.60% Principal & Interest 09/30/2018 50 Congress Mortgage Loan (6) — 31,525 (6) (6) (6) (6) 1180 Raymond Bond Payable 6,505 6,635 6.50% 6.50% Principal & Interest 09/01/2036 Central Building Mortgage Loan 27,600 27,600 One-Month LIBOR + 1.75% 2.99% Interest Only 11/13/2018 Maitland Promenade II Mortgage Loan (3) 21,830 20,877 One-Month LIBOR + 2.90% 4.13% Principal & Interest 01/01/2018 Westmoor Center Mortgage Loan (3) 61,582 62,000 One-Month LIBOR + 2.25% 3.49% Principal & Interest 02/01/2018 Plaza Buildings Senior Loan (3) 108,886 109,866 One-Month LIBOR + 1.90% 3.14% Principal & Interest 01/14/2018 424 Bedford Mortgage Loan 24,422 24,832 3.91% 3.91% Principal & Interest 10/01/2022 1180 Raymond Mortgage Loan 31,000 31,000 One-Month LIBOR + 2.25% 3.49% Interest Only 12/01/2017 KBS SOR (BVI) Holdings, Ltd. Series A Debentures (7) 274,541 251,811 4.25% 4.25% (7) 03/01/2023 Westpark Portfolio Mortgage Loan 85,200 83,200 One-Month LIBOR + 2.50% 3.74% Interest Only (8) 07/01/2020 353 Sacramento Mortgage Loan (9) — 85,500 (9) (9) (9) (9) Crown Pointe Mortgage Loan 50,500 — One-Month LIBOR + 2.60% 3.84% Interest Only 02/13/2020 125 John Carpenter Mortgage Loan 50,130 — (10) 2.99% Interest Only 10/01/2022 Total Notes and Bonds Payable principal outstanding 1,000,188 962,930 Net Premium/(Discount) on Notes and Bonds Payable (11) 124 88 Deferred financing costs, net (10,064 ) (12,394 ) Total Notes and Bonds Payable, net $ 990,248 $ 950,624 _____________________ (1) Contractual interest rate represents the interest rate in effect under the loan as of September 30, 2017 . Effective interest rate is calculated as the actual interest rate in effect as of September 30, 2017 (consisting of the contractual interest rate and contractual floor rates), using interest rate indices at September 30, 2017 , where applicable. (2) Represents the initial maturity date or the maturity date as extended as of September 30, 2017 ; subject to certain conditions, the maturity dates of certain loans may be extended beyond the date shown. (3) On November 8, 2017 , in connection with the sale of property, the Company repaid the entire principal balance and all other sums due under this loan. See note 15 , “Subsequent Events - Singapore Transaction ” for more information. (4) The Portfolio Revolving Loan Facility is secured by the 1800 West Loop Building and the Iron Point Business Park. On May 1, 2017, the Company entered into a loan modification agreement to extend the maturity date of the Portfolio Revolving Loan Facility to May 1, 2019. As a result of this modification, the Portfolio Revolving Loan Facility bears interest at a floating rate of 2.75% over one-month LIBOR. The Portfolio Revolving Loan Facility is comprised of $30.0 million of revolving debt and $45.0 million of non-revolving debt available to be used for tenant improvements, leasing commissions and capital improvements, subject to certain terms and conditions contained in the loan documents. As of September 30, 2017 , $44.6 million of non-revolving debt had been disbursed to the Company and $29.8 million of revolving debt is available for future disbursements, subject to certain conditions contained in the loan documents. On November 8, 2017 , in connection with the sale of property, the Company repaid the entire principal balance and all other sums due under this loan. See note 15 , “Subsequent Events - Singapore Transaction ” for more information. (5) On November 8, 2017 , in connection with the sale of certain properties secured by this loan, the Company repaid all but $10.0 million principal balance. The Portfolio Mortgage Loan is now only secured by one office property in the Austin Suburban Portfolio, Park Centre. See note 15 , “Subsequent Events - Singapore Transaction ” for more information. (6) On May 15, 2017, in connection with the disposition of 50 Congress Street, the Company repaid the $31.4 million outstanding principal balance due under the 50 Congress Street Mortgage Loan. (7) See “ – Israeli Bond Financing” below. (8) Represents the payment type required under the loan as of September 30, 2017 . Certain future monthly payments due under this loan also include amortizing principal payments. For more information of the Company’s contractual obligations under its notes and bonds payable, see five-year maturity table below. (9) On July 6, 2017, in connection with the partial interest sale of 353 Sacramento, the 353 Sacramento Mortgage Loan was deconsolidated from the Company's balance sheet. See note 12 , “Investment in Unconsolidated Joint Ventures” for a further discussion on the Company’s partial sale of 353 Sacramento. (10) The 125 John Carpenter Mortgage Loan bears interest at a floating rate of the greater of (a) 2.0% or (b) 175 basis points over one-month LIBOR. (11) Represents the unamortized premium/discount on notes and bonds payable due to the above- and below-market interest rates when the debt was assumed. The discount/premium is amortized over the remaining life of the notes and bonds payable. During the three and nine months ended September 30, 2017 , the Company incurred $9.6 million and $29.3 million of interest expense, respectively. Included in interest expense for the three and nine months ended September 30, 2017 was $1.0 million and $3.6 million of amortization of deferred financing costs, respectively. Additionally, during the three and nine months ended September 30, 2017 , the Company capitalized $0.6 million and $1.7 million of interest to its investments in undeveloped land, respectively. During the three and nine months ended September 30, 2016 , the Company incurred $8.0 million and $20.4 million of interest expense, respectively. Included in interest expense for the three and nine months ended September 30, 2016 was $1.1 million and $2.9 million of amortization of deferred financing costs, respectively. Additionally, during the three and nine months ended September 30, 2016 , the Company capitalized $0.5 million and $1.5 million of interest to its investments in undeveloped land, respectively. As of September 30, 2017 , the Company’s deferred financing costs were $10.1 million , net of amortization, which are included in notes and bonds payable, net on the accompanying consolidated balance sheets. As of December 31, 2016 , the Company’s deferred financing costs were $12.5 million , net of amortization, of which $12.4 million is included in notes and bonds payable, net and $0.1 million is included in prepaid expenses and other assets on the accompanying consolidated balance sheets, respectively. As of September 30, 2017 and December 31, 2016 , the Company’s interest payable was $3.0 million and $5.3 million , respectively. The following is a schedule of maturities, including principal amortization payments, for all notes and bonds payable outstanding as of September 30, 2017 (in thousands): October 1, 2017 through December 31, 2017 $ 32,706 2018 376,228 2019 158,157 2020 189,922 2021 55,787 Thereafter 187,388 $ 1,000,188 The Company’s notes payable contain financial debt covenants. As of September 30, 2017 , the Company was in compliance with all of these debt covenants. Israeli Bond Financing On March 2, 2016, KBS Strategic Opportunity BVI, a wholly owned subsidiary of the Company, filed a final prospectus with the Israel Securities Authority for a proposed offering of up to 1,000,000,000 Israeli new Shekels of Series A debentures (the “Debentures”) at an annual interest rate not to exceed 4.25% . On March 1, 2016, KBS Strategic Opportunity BVI commenced the institutional tender of the Debentures and accepted application for 842.5 million Israeli new Shekels. On March 7, 2016, KBS Strategic Opportunity BVI commenced the public tender of the Debentures and accepted 127.7 million Israeli new Shekels. In the aggregate, KBS Strategic Opportunity BVI accepted 970.2 million Israeli new Shekels (approximately $249.2 million as of March 8, 2016 ) in both the institutional and public tenders at an annual interest rate of 4.25% . KBS Strategic Opportunity BVI issued the Debentures on March 8, 2016. The terms of the Debentures require principal installment payments equal to 20% of the face value of the Debentures on March 1st of each year from 2019 to 2023. As of September 30, 2017 , the Company has one foreign currency option for an aggregate notional amount of $285.4 million to hedge its exposure to foreign currency exchange rate movements. See note 9 , “Derivative Instruments” for a further discussion on the Company’s foreign currency option. The deed of trust that governs the terms of the Debentures contains various financial covenants. As of September 30, 2017 , the Company was in compliance with all of these financial debt covenants.

DERIVATIVE INSTRUMENTS

DERIVATIVE INSTRUMENTS	9 Months Ended
	Sep. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS	DERIVATIVE INSTRUMENTS The Company enters into derivative instruments for risk management purposes to hedge its exposure to cash flow variability caused by changing interest rates and foreign currency exchange rate movements. The primary goal of the Company’s risk management practices related to interest rate risk is to prevent changes in interest rates from adversely impacting the Company’s ability to achieve its investment return objectives. The Company does not enter into derivatives for speculative purposes. The Company enters into foreign currency options and foreign currency collars to mitigate its exposure to foreign currency exchange rate movements on its bonds payable outstanding denominated in Israeli new Shekels. The foreign currency collar consists of a purchased call option to buy and a sold put option to sell Israeli new Shekels. A foreign currency collar guarantees that the exchange rate of the currency will not fluctuate beyond the range of the options’ strike prices. The foreign currency option consists of a call option to buy Israeli new Shekels. The following table summarizes the notional amount and other information related to the Company’s foreign currency collars as of December 31, 2016 . The notional amount is an indication of the extent of the Company’s involvement in each instrument at that time, but does not represent exposure to credit, interest rate or market risks (currency in thousands): Derivative Instruments Notional Amount Strike Price Trade Date Maturity Date Derivative instruments not designated as hedging instruments Foreign currency collar $ 100,000 3.72 - 3.83 ILS-USD 08/08/2016 08/08/2017 Foreign currency collar 50,000 3.67 - 3.77 ILS-USD 08/16/2016 08/16/2017 Foreign currency collar 50,000 3.68 - 3.78 ILS-USD 08/16/2016 08/16/2017 Foreign currency collar 50,000 3.67 - 3.77 ILS-USD 08/22/2016 08/22/2017 $ 250,000 On August 3, 2017, the Company terminated the foreign currency collars and as a result received $6.6 million . On August 3, 2017, the Company entered into a foreign currency option, a USD put/ILS call option, to hedge against a change in the exchange rate of the Israeli new Shekel versus the U.S. Dollar as it now has the right, but not the obligation, to purchase up to 970.2 million Israeli Shekels at the rate of ILS 3.4 per USD. The cost of the foreign currency option was $3.4 million . The following table summarizes the notional amount and other information related to the Company’s foreign currency option as of September 30, 2017 . The notional amount is an indication of the extent of the Company’s involvement in each instrument at that time, but does not represent exposure to credit, interest rate or market risks (currency in thousands): Derivative Instrument Notional Amount Strike Price Trade Date Maturity Date Derivative instrument not designated as hedging instrument Foreign currency option $ 285,361 3.40 ILS-USD 08/03/2017 08/03/2018 The Company enters into interest rate caps to mitigate its exposure to rising interest rates on its variable rate notes payable. The values of interest rate caps are primarily impacted by interest rates, market expectations about interest rates, and the remaining life of the instrument. In general, increases in interest rates, or anticipated increases in interest rates, will increase the value of interest rate caps. As the remaining life of an interest rate cap decreases, the value of the instrument will generally decrease towards zero. As of September 30, 2017 , the Company had entered into an interest rate cap, which was not designated as a hedging instrument. The following table summarizes the notional amount and other information related to the Company’s derivative instrument as of September 30, 2017 . The notional amount is an indication of the extent of the Company’s involvement in the instrument at that time, but does not represent exposure to credit, interest rate or market risks (dollars in thousands): Derivative Instrument Effective Date Maturity Date Notional Value Reference Rate Interest rate cap 02/21/2017 02/13/2020 $ 46,875 One-month LIBOR at 3.00% The following table sets forth the fair value of the Company’s derivative instruments as well as their classification on the consolidated balance sheets as of September 30, 2017 and December 31, 2016 (dollars in thousands): September 30, 2017 December 31, 2016 Derivative Instruments Balance Sheet Location Number of Instruments Fair Value Number of Instruments Fair Value Derivative instruments not designated as hedging instruments Interest rate cap Prepaid expenses and other assets 1 $ 17 1 $ 12 Foreign currency collars Other liabilities — $ — 4 $ (3,910 ) Foreign currency option Prepaid expenses and other assets 1 $ 3,884 — $ — The change in fair value of foreign currency options and collars that are not designated as cash flow hedges are recorded as foreign currency transaction gains or losses in the accompanying consolidated statements of operations. During the three months ended September 30, 2017 , the Company recognized a $8.1 million loss related to the foreign currency option and collars, which is shown net against $3.7 million of foreign currency transaction gain in the accompanying consolidated statements of operations as foreign currency transaction loss, net. During the nine months ended September 30, 2017 , the Company recognized a $10.9 million gain related to the foreign currency option and collars, which is shown net against $22.4 million of foreign currency transaction loss in the accompanying consolidated statements of operations as foreign currency transaction loss, net. During the three and nine months ended September 30, 2016 , the Company recognized $1.5 million of foreign currency transaction gain, which is shown net against $8.2 million and $6.1 million , respectively, of foreign currency transaction losses in the accompanying consolidated statements of operations as foreign currency transaction loss, net. During the three and nine months ended September 30, 2017 , the Company recorded unrealized losses of $14,000 and $102,000 , respectively, on interest rate caps, which was included in interest expense on the accompanying consolidated statements of operations.

FAIR VALUE DISCLOSURES

FAIR VALUE DISCLOSURES	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
FAIR VALUE DISCLOSURES	FAIR VALUE DISCLOSURES Under GAAP, the Company is required to measure certain financial instruments at fair value on a recurring basis. In addition, the Company is required to measure other non-financial and financial assets at fair value on a non-recurring basis (e.g., carrying value of impaired real estate loans receivable and long-lived assets). Fair value is defined as the price that would be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The GAAP fair value framework uses a three-tiered approach. Fair value measurements are classified and disclosed in one of the following three categories: • Level 1: unadjusted quoted prices in active markets that are accessible at the measurement date for identical assets or liabilities; • Level 2: quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-derived valuations in which significant inputs and significant value drivers are observable in active markets; and • Level 3: prices or valuation techniques where little or no market data is available that requires inputs that are both significant to the fair value measurement and unobservable. The fair value for certain financial instruments is derived using valuation techniques that involve significant management judgment. The price transparency of financial instruments is a key determinant of the degree of judgment involved in determining the fair value of the Company’s financial instruments. Financial instruments for which actively quoted prices or pricing parameters are available and for which markets contain orderly transactions will generally have a higher degree of price transparency than financial instruments for which markets are inactive or consist of non-orderly trades. The Company evaluates several factors when determining if a market is inactive or when market transactions are not orderly. The following is a summary of the methods and assumptions used by management in estimating the fair value of each class of financial instruments for which it is practicable to estimate the fair value: Cash and cash equivalents, rent and other receivables and accounts payable and accrued liabilities: These balances approximate their fair values due to the short maturities of these items. Real estate equity securities : The Company's real estate equity securities are presented at fair value on the accompanying consolidated balance sheets. The fair value of real estate equity securities was based on a quoted price in an active market on a major stock exchange. The Company classifies these inputs as Level 1 inputs. Real estate debt securities : The Company’s real estate debt securities are presented in the accompanying consolidated balance sheets at their amortized cost net of recorded loss reserves (if any) and not at fair value. The fair value of real estate debt securities was estimated using an internal valuation model that considers the expected cash flows for the loans, underlying collateral values (for collateral dependent loans) and estimated yield requirements of institutional investors for real estate debt securities with similar characteristics, including remaining loan term, loan-to-value, type of collateral and other credit enhancements. The Company classifies these inputs as Level 3 inputs. Notes and bonds payable: The fair values of the Company’s notes and bonds payable are estimated using a discounted cash flow analysis based on management’s estimates of current market interest rates for instruments with similar characteristics, including remaining loan term, loan-to-value ratio, type of collateral and other credit enhancements. Additionally, when determining the fair value of liabilities in circumstances in which a quoted price in an active market for an identical liability is not available, the Company measures fair value using (i) a valuation technique that uses the quoted price of the identical liability when traded as an asset or quoted prices for similar liabilities or similar liabilities when traded as assets or (ii) another valuation technique that is consistent with the principles of fair value measurement, such as the income approach or the market approach. The Company classifies these inputs as Level 3 inputs. The Company’s bonds issued in Israel are publicly traded on the Tel-Aviv Stock Exchange. The Company used the quoted price as of September 30, 2017 for the fair value of its bonds issued in Israel. The Company classifies this input as a Level 1 input. Derivative instruments : The Company’s derivative instruments are presented at fair value on the accompanying consolidated balance sheets. The valuation of these instruments is determined using a proprietary model that utilizes observable inputs. As such, the Company classifies these inputs as Level 2 inputs. The fair value of interest rate caps (floors) are determined using the market standard methodology of discounting the future expected cash payments (receipts) which would occur if variable interest rates rise above (below) the strike rate of the caps (floors). The variable interest rates used in the calculation of projected payments (receipts) on the cap (floor) are based on an expectation of future interest rates derived from observed market interest rate curves and volatilities. The fair value of foreign currency option is based on a Black-Scholes model tailored for currency derivatives. The following were the face values, carrying amounts and fair values of the Company’s financial instruments as of September 30, 2017 and December 31, 2016 , which carrying amounts do not approximate the fair values (in thousands): September 30, 2017 December 31, 2016 Face Value Carrying Amount Fair Value Face Value Carrying Amount Fair Value Financial asset: Real estate debt securities $ 17,500 $ 17,642 $ 17,358 $ 5,000 $ 4,683 $ 4,683 Financial liabilities: Notes and bond payable $ 725,647 $ 722,673 $ 727,521 $ 711,119 $ 707,169 $ 711,425 KBS SOR (BVI) Holdings, Ltd. Series A Debentures $ 274,541 $ 267,575 $ 288,817 $ 251,811 $ 243,455 $ 253,120 Disclosure of the fair value of financial instruments is based on pertinent information available to the Company as of the period end and requires a significant amount of judgment. This has made the estimation of fair values difficult and, therefore, both the actual results and the Company’s estimate of value at a future date could be materially different. As of September 30, 2017 , the Company measured the following assets at fair value (in thousands): Fair Value Measurements Using Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Recurring Basis: Real estate equity securities $ 47,022 $ 47,022 $ — $ — Asset derivatives - interest rate caps $ 17 $ — $ 17 $ — Asset derivative - foreign currency option $ 3,884 $ — $ 3,884 $ —

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS	9 Months Ended
	Sep. 30, 2017
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS The Advisory Agreement entitles the Advisor to specified fees upon the provision of certain services with regard to the investment of funds in real estate and real estate-related investments and the disposition of real estate and real estate-related investments (including the discounted payoff of non-performing loans) among other services, as well as reimbursement of certain costs incurred by the Advisor in providing services to the Company. The Advisory Agreement may also entitle the Advisor to certain back-end cash flow participation fees. The Company also entered into a fee reimbursement agreement (the “AIP Reimbursement Agreement”) with KBS Capital Markets Group LLC, the dealer manager for the Company’s initial public offering (the “Dealer Manager”), pursuant to which the Company agreed to reimburse the Dealer Manager for certain fees and expenses it incurs for administering the Company’s participation in the Depository Trust & Clearing Corporation Alternative Investment Product Platform with respect to certain accounts of the Company’s investors serviced through the platform. The Advisor and Dealer Manager also serve as the advisor and dealer manager, respectively, for KBS Real Estate Investment Trust, Inc. (“KBS REIT I”), KBS Real Estate Investment Trust II, Inc. (“KBS REIT II”), KBS Real Estate Investment Trust III, Inc. (“KBS REIT III”), KBS Legacy Partners Apartment REIT, Inc. (“KBS Legacy Partners Apartment REIT”), KBS Strategic Opportunity REIT II, Inc. (“KBS Strategic Opportunity REIT II”) and KBS Growth & Income REIT, Inc. (“KBS Growth & Income REIT”). On January 6, 2014, the Company, together with KBS REIT I, KBS REIT II, KBS REIT III, KBS Legacy Partners Apartment REIT, KBS Strategic Opportunity REIT II, the Dealer Manager, the Advisor and other KBS-affiliated entities, entered into an errors and omissions and directors and officers liability insurance program where the lower tiers of coverage are shared. The cost of these lower tiers is allocated by the Advisor and its insurance broker among each of the various entities covered by the plan, and is billed directly to each entity. The allocation of these shared coverage costs is proportionate to the pricing by the insurance marketplace for the first tiers of directors and officers liability coverage purchased individually by each REIT. The Advisor’s and the Dealer Manager’s portion of the shared lower tiers’ cost is proportionate to the respective entities’ prior cost for the errors and omissions insurance. In June 2015, KBS Growth & Income REIT was added to the insurance program at terms similar to those described above. In June 2017, the Company renewed its participation in the program, and the program is effective through June 30, 2018. As KBS REIT I is implementing its plan of liquidation, at renewal in June 2017, KBS REIT I elected to cease participation in the program and obtain separate insurance coverage. During the three and nine months ended September 30, 2017 and 2016 , no other business transactions occurred between the Company and these other KBS-sponsored programs. Pursuant to the terms of these agreements, summarized below are the related-party costs incurred by the Company for the three and nine months ended September 30, 2017 and 2016 , respectively, and any related amounts payable as of September 30, 2017 and December 31, 2016 (in thousands): Incurred Payable as of Three Months Ended September 30, Nine Months Ended September 30, September 30, 2017 December 31, 2016 2017 2016 2017 2016 Expensed Asset management fees $ 2,800 $ 2,639 $ 8,404 6,932 $ — $ — Acquisition fees on real estate (1) — 1,690 — 2,964 — — Reimbursable operating expenses (2) 51 57 184 170 33 55 Disposition fees (3) — — 785 279 — — Capitalized Acquisition fees on real estate (1) 71 — 907 — — — Acquisition fees on real estate equity securities 43 — 429 — — — $ 2,965 $ 4,386 $ 10,709 $ 10,345 $ 33 $ 55 _____________________ (1) As a result of the adoption of ASU No. 2017-01, the Company’s acquisitions of real estate properties beginning January 1, 2017 generally qualify as an asset acquisition (as opposed to a business combination). Acquisition fees associated with asset acquisitions will be capitalized, while costs associated with business combinations will continue to be expensed as incurred. (2) The Advisor may seek reimbursement for certain employee costs under the Advisory Agreement. The Company has reimbursed the Advisor for the Company’s allocable portion of the salaries, benefits and overhead of internal audit department personnel providing services to the Company. These amounts totaled $49,000 and $168,000 for the three and nine months ended September 30, 2017 , respectively, and $30,000 and $114,000 for the three and nine months ended September 30, 2016 , respectively, and were the only employee costs reimbursed under the Advisory Agreement during these periods. The Company will not reimburse for employee costs in connection with services for which the Advisor earns acquisition, origination or disposition fees (other than reimbursement of travel and communication expenses) or for the salaries or benefits the Advisor or its affiliates may pay to the Company’s executive officers. In addition to the amounts above, the Company reimburses the Advisor for certain of the Company's direct costs incurred from third parties that were initially paid by the Advisor on behalf of the Company. (3) Disposition fees with respect to real estate sold are included in the gain on sale of real estate in the accompanying consolidated statements of operations. Disposition fees with respect to the assignment of the Company's real estate loan receivable are included in general and administrative expenses in the accompanying consolidated statements of operations. During the nine months ended September 30, 2017 , the Advisor reimbursed the Company $0.4 million for expenses incurred to evaluate certain strategic transactions for which the Advisor has agreed to reimburse the Company and $0.1 million for a property insurance rebate. During the nine months ended September 30, 2016 , the Advisor reimbursed the Company $0.1 million for a property insurance rebate and $0.1 million for legal and professional fees. Pursuant to the Waiver Agreement, the Advisor waived any right it may have had to receive a disposition fee in connection with the 353 Sacramento Transaction and also waived its rights to future acquisition fees in an amount equal to 45% of the acquisition fees paid to the Advisor in connection with the Company’s original purchase of 353 Sacramento in July of 2016. Accordingly, the Advisor waived $0.8 million of acquisition fees for the purchase of 125 John Carpenter. In connection with the 353 Sacramento Transaction, the Company paid a $0.1 million broker commission to Monarch Global Partners, LLC. The son of a member of the board of directors of KBS Strategic Opportunity BVI is a partner at Monarch Global Partners, LLC.

INVESTMENT IN UNCONSOLIDATED JO

INVESTMENT IN UNCONSOLIDATED JOINT VENTURES	9 Months Ended
	Sep. 30, 2017
Equity Method Investments and Joint Ventures [Abstract]
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES	INVESTMENT IN UNCONSOLIDATED JOINT VENTURES As of September 30, 2017 and December 31, 2016 , the Company’s investments in unconsolidated joint ventures were composed of the following (dollars in thousands): Investment Balance at Joint Venture Number of Properties Location Ownership % September 30, 2017 December 31, 2016 NIP Joint Venture 8 Various Less than 5.0% $ 4,317 $ 5,305 110 William Joint Venture 1 New York, New York 60.0% 8,668 70,544 353 Sacramento Joint Venture 1 San Francisco, California 55.0% 45,344 — $ 58,329 $ 75,849 Investment in National Industrial Portfolio Joint Venture On May 18, 2012, the Company, through an indirect wholly owned subsidiary, entered into a joint venture (the “NIP Joint Venture”) with OCM NIP JV Holdings, L.P. and HC KBS NIP JV, LLC (“HC-KBS”). As of September 30, 2017 , the NIP Joint Venture owned eight industrial properties and a master lease with respect to another industrial property encompassing 4.4 million square feet. The Company made an initial capital contribution of $8.0 million which represents less than a 5.0% ownership interest in the NIP Joint Venture as of September 30, 2017 . The Company has virtually no influence over the NIP Joint Venture’s operations, financial policies or decision making. Accordingly, the Company has accounted for its investment in the NIP Joint Venture under the cost method of accounting. Income, losses and distributions from the NIP Joint Venture are generally allocated among the members based on their respective equity interests. KBS REIT I, an affiliate of the Advisor, is a member of HC-KBS and has a participation interest in certain future potential profits generated by the NIP Joint Venture. However, KBS REIT I does not have any equity interest in the NIP Joint Venture. None of the other joint venture partners are affiliated with the Company or the Advisor. As of September 30, 2017 and December 31, 2016 , the book value of the Company’s investment in the NIP Joint Venture was $4.3 million and $5.3 million , respectively. During the three months ended September 30, 2017 , the Company did not receive any distributions related to its investment in the NIP Joint Venture. During the nine months ended September 30, 2017 , the Company received a distribution of $2.9 million related to its investment in the NIP Joint Venture. The Company recognized $1.9 million of income distributions and $1.0 million of return of capital from the NIP Joint Venture. During the three and nine months ended September 30, 2016 , the Company did not receive any distributions related to its investment in the NIP Joint Venture. Investment in 110 William Joint Venture On December 23, 2013, the Company, through an indirect wholly owned subsidiary, entered into an agreement with SREF III 110 William JV, LLC (the “110 William JV Partner”) to form a joint venture (the “110 William Joint Venture”). On May 2, 2014, the 110 William Joint Venture acquired an office property containing 928,157 rentable square feet located on approximately 0.8 acres of land in New York, New York (“110 William Street”). Each of the Company and the 110 William JV Partner hold a 60% and 40% ownership interest in the 110 William Joint Venture, respectively. The Company exercises significant influence over the operations, financial policies and decision making with respect to the 110 William Joint Venture but significant decisions require approval from both members. Accordingly, the Company has accounted for its investment in the 110 William Joint Venture under the equity method of accounting. Income, losses, contributions and distributions are generally allocated based on the members’ respective equity interests. As of September 30, 2017 and December 31, 2016 , the book value of the Company’s investment in the 110 William Joint Venture was $8.7 million and $70.5 million , respectively, which includes $1.5 million of unamortized acquisition fees and expenses incurred directly by the Company. During the nine months ended September 30, 2017 , the 110 William Joint Venture made a $58.2 million return of capital distribution to the Company and a $38.8 million return of capital distribution to the 110 William JV Partner funded with proceeds from the 110 William refinancing discussed below. Summarized financial information for the 110 William Joint Venture follows (in thousands): September 30, 2017 December 31, 2016 Assets: Real estate assets, net of accumulated depreciation and amortization $ 252,428 $ 262,192 Other assets 31,135 23,355 Total assets $ 283,563 $ 285,547 Liabilities and equity: Notes payable, net (1) $ 259,123 $ 157,628 Other liabilities 12,468 12,872 Partners’ capital 11,972 115,047 Total liabilities and equity $ 283,563 $ 285,547 _____________________ (1) See “- 110 William Joint Venture Refinance” below. Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 Revenues $ 9,614 $ 8,461 $ 27,328 $ 25,100 Expenses: Operating, maintenance, and management 2,577 3,162 7,343 8,120 Real estate taxes and insurance 1,637 1,535 4,725 4,502 Depreciation and amortization 4,664 3,563 12,277 9,831 Interest expense 3,951 1,517 9,150 4,541 Total expenses 12,829 9,777 33,495 26,994 Other income 14 16 42 48 Net loss $ (3,201 ) $ (1,300 ) $ (6,125 ) $ (1,846 ) Company’s equity in loss of unconsolidated joint venture $ (1,930 ) $ (791 ) $ (3,706 ) $ (1,139 ) 110 William Joint Venture Refinance On May 2, 2014, in connection with the acquisition of 110 William Street, the 110 William Joint Venture assumed a mortgage loan with a face amount of $141.5 million and a mezzanine loan with a face amount of $20.0 million (the “110 William Street Existing Loans”). On March 6, 2017, the 110 William Joint Venture closed the refinancing of the 110 William Street Existing Loans (the “Refinancing”). The 110 William Joint Venture repaid $156.0 million of principal related to the 110 William Street Existing Loans. The Refinancing was comprised of the following loans from unaffiliated lenders: (i) a mortgage loan in the maximum amount of up to $232.3 million from Morgan Stanley Bank, N.A., a national banking association (the “110 William Street Mortgage Loan”), (ii) a senior mezzanine loan in the maximum amount of up to $33.8 million from Morgan Stanley Mortgage Capital Holdings LLC, a New York limited liability company (the “110 William Street Senior Mezzanine Loan”), and (iii) a junior mezzanine loan in the maximum amount of up to $33.8 million from Morgan Stanley Mortgage Capital Holdings LLC, a New York limited liability company (the “110 William Street Junior Mezzanine Loan”). The loans under the Refinancing mature on March 7, 2019, with three one -year extension options. The 110 William Street Mortgage Loan bears interest at a floating rate of 2.2472% over one-month LIBOR. The 110 William Street Senior Mezzanine Loan and the 110 William Street Junior Mezzanine Loan bear interest at a floating rate of 6.25% over one-month LIBOR. The 110 William Joint Venture entered into three interest rate caps that effectively limit one-month LIBOR at 3.00% on $275.0 million of the Refinancing amount as of the effective date, up to $300.0 million , accreting according to a notional schedule, effective March 6, 2017 through March 7, 2019. The loans under the Refinancing have monthly payments that are interest-only with the entire unpaid principal balance and all outstanding interest and fees due at maturity. The 110 William Joint Venture has the right to prepay the loans in whole at any time or in part from time to time to the extent necessary, subject to the payment of certain expenses potentially incurred by the lender as a result of the prepayment, the payment of a prepayment premium and breakage costs in certain circumstances, and certain other conditions contained in the loan documents. At closing, $205.0 million had been disbursed from the 110 William Street Mortgage Loan to the 110 William Joint Venture with $27.3 million remaining available for future disbursements to be used for tenant improvements, leasing commissions and capital improvements, subject to certain terms and conditions contained in the loan documents. At closing, $29.85 million had been disbursed from the 110 William Street Senior Mezzanine Loan to the 110 William Joint Venture and $29.85 million had been disbursed from the 110 William Junior Mezzanine Loan to the 110 William Joint Venture, with $4.0 million remaining available under the 110 William Street Senior Mezzanine Loan and $4.0 million remaining available under the 110 William Street Junior Mezzanine Loan for future disbursements to be used for tenant improvements, leasing commissions and capital improvements, subject to certain terms and conditions contained in the loan documents under the 110 William Street Senior Mezzanine Loan and the 110 William Street Junior Mezzanine Loan. Investment in 353 Sacramento Joint Venture On July 6, 2017, the Company, through an indirect wholly owned subsidiary, entered into an agreement with the Migdal Members to form the 353 Sacramento Joint Venture. On July 6, 2017, the Company sold a 45% equity interest in an entity that owns 353 Sacramento to the Migdal Members. The sale resulted in 353 Sacramento being owned by the 353 Sacramento Joint Venture, in which the Company indirectly owns 55% of the equity interests and the Migdal Members indirectly own 45% in the aggregate of the equity interests. The Company exercises significant influence over the operations, financial policies and decision making with respect to the 353 Sacramento Joint Venture but significant decisions require approval from both members. Accordingly, the Company has accounted for its investment in the 353 Sacramento Joint Venture under the equity method of accounting. Income, losses, contributions and distributions are generally allocated based on the members’ respective equity interests. As of September 30, 2017 , the book value of the Company’s investment in the 353 Sacramento Joint Venture was $45.3 million . During the three and nine months ended September 30, 2017 , the Company did not receive any distributions related to its investment in the 353 Sacramento Joint Venture. Summarized financial information for the 353 Sacramento Joint Venture follows (in thousands): September 30, 2017 Assets: Real estate assets, net of accumulated depreciation and amortization $ 170,477 Other assets 5,438 Total assets $ 175,915 Liabilities and equity: Notes payable, net $ 87,605 Other liabilities 6,358 Partners’ capital 81,952 Total liabilities and equity $ 175,915 For the Period from July 6, 2017 to September 30, 2017 Revenues $ 3,507 Expenses: Operating, maintenance, and management 936 Real estate taxes and insurance 603 Depreciation and amortization 1,724 Interest expense 1,138 Total expenses 4,401 Net loss $ (894 ) Company’s equity in loss of unconsolidated joint venture $ (222 )

SUPPLEMENTAL CASH FLOW AND SIGN

SUPPLEMENTAL CASH FLOW AND SIGNIFICANT NONCASH TRANSACTION DISCLOSURES	9 Months Ended
	Sep. 30, 2017
Supplemental Cash Flow and Significant Noncash Transaction Disclosures [Abstract]
SUPPLEMENTAL CASH FLOW AND SIGNIFICANT NONCASH TRANSACTION DISCLOSURES	SUPPLEMENTAL CASH FLOW AND SIGNIFICANT NONCASH TRANSACTION DISCLOSURES Supplemental cash flow and significant noncash transaction disclosures were as follows (in thousands): Nine Months Ended September 30, 2017 2016 Supplemental Disclosure of Cash Flow Information: Interest paid, net of capitalized interest of $1,732 and $1,478 for the nine months ended September 30, 2017 and 2016 , respectively $ 27,732 $ 16,146 Supplemental Disclosure of Significant Noncash Transactions: Assets and liabilities deconsolidated in connection with the 353 Sacramento partial sale: Real estate, net 170,586 — Rents and other receivables, net 1,244 — Prepaid expenses and other assets 555 — Notes payable, net 87,132 — Accounts payable and accrued liabilities 1,574 — Below-market leases, net 2,960 — Other liabilities 924 — Application of escrow deposits to acquisition of real estate 2,000 — Increase in accrued improvements to real estate 1,319 1,686 Distributions paid to common stockholders through common stock issuances pursuant to the dividend reinvestment plan 8,666 9,520

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Economic Dependency The Company is dependent on the Advisor for certain services that are essential to the Company, including the identification, evaluation, negotiation, origination, acquisition and disposition of investments; management of the daily operations of the Company’s investment portfolio; and other general and administrative responsibilities. In the event that the Advisor is unable to provide these services, the Company will be required to obtain such services from other sources. Environmental As an owner of real estate, the Company is subject to various environmental laws of federal, state and local governments. Although there can be no assurance, the Company is not aware of any environmental liability that could have a material adverse effect on its financial condition or results of operations as of September 30, 2017 . However, changes in applicable environmental laws and regulations, the uses and conditions of properties in the vicinity of the Company’s properties, the activities of its tenants and other environmental conditions of which the Company is unaware with respect to the properties could result in future environmental liabilities. Legal Matters From time to time, the Company is a party to legal proceedings that arise in the ordinary course of its business. Management is not aware of any legal proceedings of which the outcome is probable or reasonably possible to have a material adverse effect on the Company’s results of operations or financial condition, which would require accrual or disclosure of the contingency and the possible range of loss. Additionally, the Company has not recorded any loss contingencies related to legal proceedings in which the potential loss is deemed to be remote.

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS The Company evaluates subsequent events up until the date the consolidated financial statements are issued. Singapore Transaction On November 8, 2017 , the Company, through 11 wholly owned subsidiaries, sold 11 of its properties (the “Singapore Portfolio”) to various subsidiaries of Keppel-KBS US REIT, a newly formed Singapore real estate investment trust (the “SREIT”) that was listed on the Singapore Stock Exchange (the “Singapore Transaction”). The sale price of the Singapore Portfolio was $804.0 million , before third-party closing costs of approximately $7.7 million and excluding any disposition fees payable to the Advisor. The Singapore Portfolio consists of the following properties: 1800 West Loop, Westech 360 (part of the Austin Suburban Portfolio), Great Hills Plaza (part of the Austin Suburban Portfolio), Westmoor Center, Iron Point Business Park, the Plaza Buildings, Bellevue Technology Center, Northridge Center I and II, West Loop I and II, Powers Ferry Landing East and Maitland Promenade II. As of September 30, 2017 , the carrying value of the Singapore Portfolio was $546.5 million . In connection with the Singapore Transaction, the Company repaid $401.7 million of outstanding debt secured by the properties in the Singapore Portfolio. The Company also used approximately $52.5 million of the proceeds to acquire units in the SREIT representing a 9.5% ownership interest. Currently, the SREIT does not own any properties other than the Singapore Portfolio. The SREIT was established with the investment strategy of principally investing, directly or indirectly, in a diversified portfolio of income-producing commercial assets and real estate-related assets in the key growth markets of the United States. The SREIT will be externally managed by a joint venture (the “Manager”) between (i) an entity in which Keith D. Hall, the Company’s Chief Executive Officer and a director, and Peter McMillan III, the Company’s President and Chairman of the board of directors, have an indirect ownership interest and (ii) Keppel Capital Holding Pte. Ltd., which is not affiliated with the Company. The SREIT is expected to pay certain purchase and sale commissions and asset management fees to the Manager in exchange for the provision of certain management services.

SUMMARY OF SIGNIFICANT ACCOUN23

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation	The accompanying unaudited consolidated financial statements and condensed notes thereto have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information as contained within the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) and the rules and regulations of the SEC, including the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, the unaudited consolidated financial statements do not include all of the information and footnotes required by GAAP for audited financial statements. In the opinion of management, the financial statements for the unaudited interim periods presented include all adjustments, which are of a normal and recurring nature, necessary for a fair and consistent presentation of the results for such periods. Operating results for the three and nine months ended September 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017 .
Principles of Consolidation	The consolidated financial statements include the accounts of the Company, REIT Holdings, the Operating Partnership, KBS Strategic Opportunity BVI and their direct and indirect wholly owned subsidiaries, and joint ventures in which the Company has a controlling interest. All significant intercompany balances and transactions are eliminated in consolidation.
Use of Estimates	The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could materially differ from those estimates.
Real Estate Equity Securities	The Company determines the appropriate classification for real estate equity securities at acquisition (on the trade date) and reevaluates such designation as of each balance sheet date. As of September 30, 2017 , the Company classified its investment in real estate equity securities as available-for-sale as the Company intends to hold the securities for the purpose of collecting dividend income and for longer term price appreciation. These investments are carried at their estimated fair value based on quoted market prices for the security. Transaction costs that are directly attributable to the acquisition of real estate equity securities are capitalized to its cost basis. Unrealized gains and losses are reported in accumulated other comprehensive income (loss). Upon the sale of a security, the previously recognized unrealized gain (loss) would be reversed out of accumulated other comprehensive income (loss) and the actual realized gain (loss) recognized in earnings. Dividend income is recognized on an accrual basis based on eligible shares as of the ex-dividend date. Any non-temporary decline in the market value of an available-for-sale real estate equity security below cost results in a reduction in the carrying amount to fair value. The impairment is charged to earnings and a new cost basis for the real estate security is established. When a real estate equity security is impaired, the Company considers whether it has the ability and intent to hold the investment for a time sufficient to allow for any anticipated recovery in market value and considers whether evidence indicating the cost of the investment being recoverable outweighs evidence to the contrary. Evidence considered in this assessment includes the reasons for the impairment, the severity and duration of the impairment, changes in value subsequent to period end and forecasted performance of the investee.
Reclassifications	Certain amounts in the Company’s prior period consolidated financial statements have been reclassified to conform to the current period presentation. These reclassifications have not changed the results of operations of the prior period. During the year ended December 31, 2016, the Company elected to early adopt ASU No. 2016-18 (as defined below). As a result, the Company no longer presents transfers between cash and restricted cash in the consolidated statements of cash flows. Instead, restricted cash is included with cash and cash equivalents when reconciling the beginning of period and end of period total amounts shown on the consolidated statements of cash flows. During the nine months ended September 30, 2017 , the Company disposed of one office property. As a result, certain assets and liabilities were reclassified to held for sale on the consolidated balance sheets for all periods presented.
Redeemable Common Stock	On December 8, 2016, the Company adopted a tenth amended and restated share redemption program (the “Tenth Amended Share Redemption Program”) that may enable stockholders to sell their shares to the Company in limited circumstances. Pursuant to the Tenth Amended Share Redemption Program, except for redemptions made upon a stockholder’s death, “qualifying disability” or “determination of incompetence,” the price at which we will redeem shares is 95% of our most recent estimated value per share as of the applicable redemption date. The Tenth Amended Share Redemption Program was effective on December 30, 2016. Pursuant to the share redemption program there are several limitations on the Company’s ability to redeem shares: • Unless the shares are being redeemed in connection with a stockholder’s death, “qualifying disability” or “determination of incompetence” (each as defined under the share redemption program), the Company may not redeem shares until the stockholder has held the shares for one year. • The Company may not redeem more than $3.0 million of shares in a given quarter (excluding shares redeemed in connection with a stockholder’s death, “qualifying disability” or “determination of incompetence”). To the extent that the Company redeems less than $3.0 million of shares (excluding shares redeemed in connection with a stockholder’s death, “qualifying disability” or “determination of incompetence”) in a given fiscal quarter, any remaining excess capacity to redeem shares in such fiscal quarter will be added to the Company’s capacity to otherwise redeem shares (excluding shares redeemed in connection with a stockholder’s death, “qualifying disability” or “determination of incompetence”) during succeeding fiscal quarters. The last $1.0 million of net proceeds from the dividend reinvestment plan during the prior year is reserved exclusively for shares redeemed in connection with a stockholder’s death, “qualifying disability,” or “determination of incompetence.” The share redemption plan also provides that, to the extent that in the last month of any calendar year the amount of redemption requests in connection with a stockholder’s death, “qualifying disability or “determination of incompetence” is less than the $1.0 million reserved for such redemptions under the share redemption plan, any excess funds may be used to redeem shares not requested in connection with a stockholder’s death, “qualifying disability or “determination of incompetence” during such month. The Company may increase or decrease this limit upon ten business days’ notice to stockholders. The Company’s board of directors may approve an increase in this limit to the extent that the Company has received proceeds from asset sales or the refinancing of debt or for any other reason deemed appropriate by the board of directors. • During any calendar year, the Company may redeem no more than 5% of the weighted-average number of shares outstanding during the prior calendar year. • The Company has no obligation to redeem shares if the redemption would violate the restrictions on distributions under Maryland law, which prohibits distributions that would cause a corporation to fail to meet statutory tests of solvency. The Company’s board of directors may amend, suspend or terminate the share redemption program with ten business days’ notice to its stockholders. On September 14, 2017 , the Company commenced a self-tender offer (the “SOR Offer”) for up to 3,553,660 shares of common stock at a price of $14.07 per share, or approximately $50.0 million of shares. On October 18, 2017 , the Company increased the number of shares accepted for payment in the SOR Offer by up to 1,135,912 shares at a price of $14.07 per share, or approximately $16.0 million of shares. On October 23, 2017 , the Company accepted for purchase 4,688,671 shares for an aggregate cost of $66.0 million , excluding fees and expenses related to the SOR Offer. Because of the SOR Offer, the Tenth Amended Share Redemption Program was suspended from September 29, 2017 through October 31, 2017 , meaning no redemptions were made in September or October (including those requested following a stockholder’s death, “qualifying disability” or “determination of incompetence”). The Company cancelled all outstanding redemption requests under the SRP as of the commencement of the SOR Offer and was not accepting any redemption requests under the SRP during the term of the SOR Offer. The Company records amounts that are redeemable under the share redemption program and the SOR Offer as redeemable common stock in its consolidated balance sheets because the shares are redeemable at the option of the holder to the extent there is sufficient capacity under the share redemption program and therefore their redemption is outside the control of the Company. However, because the amounts that can be redeemed will be determinable and only contingent on an event that is likely to occur (e.g., the passage of time), the Company presents the net proceeds from the current year and prior year DRP, net of current year redemptions, as redeemable common stock in its consolidated balance sheets. The Company classifies as liabilities financial instruments that represent a mandatory obligation of the Company to redeem shares. The Company’s redeemable common shares are contingently redeemable at the option of the holder. When the Company determines it has a mandatory obligation to repurchase shares under the share redemption program, it will reclassify such obligations from temporary equity to a liability based upon their respective settlement values. The Company limits the dollar value of shares that may be redeemed under the program as described above. The Company recorded $11.4 million of other liabilities on the Company’s balance sheet as of September 30, 2017 related to shares submitted for tender under the SOR Offer as of September 30, 2017 . The Company recorded $12.6 million of other liabilities on the Company’s balance sheet as of December 31, 2016 related to unfulfilled redemption requests received in good order under the share redemption program as of December 31, 2016 . As of September 30, 2017 , the Company recorded $52.0 million of redeemable common stock consisting of (i) $38.6 million of the amount available to tender related to the SOR Offer (excludes shares already submitted for tender as of September 30, 2017 ), (ii) $4.7 million available for all redemptions in the remainder of 2017, including shares that are redeemed in connection with a stockholders’ death, “qualifying disability” or “determination of incompetence” based on the amount of net proceeds raised from the sale of shares under the dividend reinvestment plan during 2016 and (iii) $8.7 million available for all redemptions in 2018, including shares that are redeemed in connection with a stockholders’ death, “qualifying disability” or “determination of incompetence” based on the amount of net proceeds raised from the sale of shares under the dividend reinvestment plan during 2017.
Segments	The Company has invested in non-performing loans, opportunistic real estate and other real estate-related assets. In general, the Company intends to hold its investments in non-performing loans, opportunistic real estate and other real estate‑related assets for capital appreciation. Traditional performance metrics of non-performing loans, opportunistic real estate and other real estate-related assets may not be meaningful as these investments are generally non-stabilized and do not provide a consistent stream of interest income or rental revenue. These investments exhibit similar long-term financial performance and have similar economic characteristics. These investments typically involve a higher degree of risk and do not provide a constant stream of ongoing cash flows. As a result, the Company’s management views non-performing loans, opportunistic real estate and other real estate-related assets as similar investments. Substantially all of its revenue and net income (loss) is from non-performing loans, opportunistic real estate and other real estate-related assets, and therefore, the Company currently aggregates its operating segments into one reportable business segment.
Per Share Data	Basic net income (loss) per share of common stock is calculated by dividing net income (loss) attributable to common stockholders by the weighted-average number of shares of common stock issued and outstanding during such period. Diluted net income (loss) per share of common stock equals basic net income (loss) per share of common stock as there were no potentially dilutive securities outstanding during the three and nine months ended September 30, 2017 and 2016 . Distributions declared per share were $0.09452055 and $0.28047945 during the three and nine months ended September 30, 2017 , respectively, and $0.09426230 and $0.28073770 during the three and nine months ended September 30, 2016
Square Footage, Occupancy and Other Measures	Any references to square footage, occupancy or annualized base rent are unaudited and outside the scope of the Company’s independent registered public accounting firm’s review of the Company’s financial statements in accordance with the standards of the United States Public Company Accounting Oversight Board.
Recently Issued Accounting Standards Updates	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) (“ASU No. 2014-09”). ASU No. 2014-09 requires an entity to recognize the revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. ASU No. 2014-09 supersedes the revenue requirements in Revenue Recognition (Topic 605) and most industry-specific guidance throughout the Industry Topics of the Codification. ASU No. 2014-09 does not apply to lease contracts within the scope of Leases (Topic 840). ASU No. 2014-09 was to be effective for fiscal years, and interim periods within those years, beginning after December 15, 2016, and is to be applied retrospectively, with early application not permitted. In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date (“ASU No. 2015-14”), which defers the effective date of ASU No. 2014-09 by one year. Early adoption is permitted but not before the original effective date. The primary source of revenue for the Company is generated through leasing arrangements, which are excluded from this standard. The Company’s revenues that may be impacted by this standard primarily include other operating income, sales of real estate, including land parcels and operating properties, and other ancillary income earned at its properties. In 2016, other operating income and other ancillary income were approximately 5% of consolidated revenue. The Company is in the process of evaluating how this standard will impact sales of real estate. The Company continues to evaluate the impact that the standard will have on its consolidated financial statements. The Company expects to adopt the standard using the modified retrospective approach, which requires a cumulative effect adjustment as of the date of the adoption. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities (“ASU No. 2016-01”). The amendments in ASU No. 2016-01 address certain aspects of recognition, measurement, presentation and disclosure of financial instruments. ASU No. 2016-01 primarily affects accounting for equity investments and financial liabilities where the fair value option has been elected. ASU No. 2016-01 supersedes the guidance to classify equity securities with readily determinable fair values into different categories (that is, trading or available-for-sale) and requires equity securities (including other ownership interests, such as partnerships, unincorporated joint ventures, and limited liability companies) to be measured at fair value with changes in the fair value recognized through net income. ASU No. 2016-01 also requires entities to present financial assets and financial liabilities separately, grouped by measurement category and form of financial asset in the balance sheet or in the accompanying notes to the financial statements. ASU No. 2016-01 is effective for annual periods beginning after December 15, 2017, including interim periods within those fiscal years. Early application of certain provisions of the standard is permitted for financial statements that have not been previously issued. Upon adoption, the Company will be required to record net unrealized gain or loss on real estate equity securities in earnings and record a cumulative effect adjustment to the balance sheet. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) (“ASU No. 2016-02”). The amendments in ASU No. 2016-02 change the existing accounting standards for lease accounting, including requiring lessees to recognize most leases on their balance sheets and making targeted changes to lessor accounting. ASU No. 2016-02 is effective for annual periods beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption of ASU No. 2016-02 is permitted. The new leases standard requires a modified retrospective transition approach for all leases existing at, or entered into after, the date of initial application, with an option to use certain transition relief. The Company is currently evaluating the impact of adopting the new leases standard on its consolidated financial statements. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses of Financial Instruments (“ASU No. 2016-13”). ASU No. 2016-13 affects entities holding financial assets and net investments in leases that are not accounted for at fair value through net income. The amendments in ASU No. 2016-13 require a financial asset (or a group of financial assets) measured at amortized cost basis to be presented at the net amount expected to be collected. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of the financial asset(s) to present the net carrying value at the amount expected to be collected on the financial asset. ASU No. 2016-13 also amends the impairment model for available-for-sale securities. An entity will recognize an allowance for credit losses on available-for-sale debt securities as a contra-account to the amortized cost basis rather than as a direct reduction of the amortized cost basis of the investment, as is currently required. ASU No. 2016-13 also requires new disclosures. For financial assets measured at amortized cost, an entity will be required to disclose information about how it developed its allowance for credit losses, including changes in the factors that influenced management’s estimate of expected credit losses and the reasons for those changes. For financing receivables and net investments in leases measured at amortized cost, an entity will be required to further disaggregate the information it currently discloses about the credit quality of these assets by year of the asset’s origination for as many as five annual periods. For available-for-sale securities, an entity will be required to provide a roll-forward of the allowance for credit losses and an aging analysis for securities that are past due. ASU No. 2016-13 is effective for annual periods beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company is still evaluating the impact of adopting ASU No. 2016-13 on its financial statements. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (“ASU No. 2016-15”). ASU No. 2016-15 is intended to reduce diversity in practice in how certain transactions are classified in the statement of cash flows. The amendments in ASU No. 2016-15 provide guidance on eight specific cash flow issues, including the following that are or may be relevant to the Company: (a) Cash payments for debt prepayment or debt extinguishment costs should be classified as cash outflows for financing activities; (b) Cash payments relating to contingent consideration made soon after an acquisition’s consummation date (i.e., approximately three months or less) should be classified as cash outflows for investing activities. Payments made thereafter should be classified as cash outflows for financing activities up to the amount of the original contingent consideration liability. Payments made in excess of the amount of the original contingent consideration liability should be classified as cash outflows for operating activities; (c) Cash payments received from the settlement of insurance claims should be classified on the basis of the nature of the loss (or each component loss, if an entity receives a lump-sum settlement); and (d) Relating to distributions received from equity method investments, ASU No. 2016-15 provides an accounting policy election for classifying distributions received from equity method investments. Such amounts can be classified using a (1) cumulative earnings approach, or (2) nature of distribution approach. Under the cumulative earnings approach, an investor would compare the distributions received to its cumulative equity method earnings since inception. Any distributions received up to the amount of cumulative equity earnings would be considered a return on investment and classified in operating activities. Any excess distributions would be considered a return of investment and classified in investing activities. Alternatively, an investor can choose to classify the distributions based on the nature of activities of the investee that generated the distribution. If the necessary information is subsequently not available for an investee to determine the nature of the activities, the entity should use the cumulative earnings approach for that investee and report a change in accounting principle on a retrospective basis; (e) In the absence of specific guidance, an entity should classify each separately identifiable cash source and use on the basis of the nature of the underlying cash flows. For cash flows with aspects of more than one class that cannot be separated, the classification should be based on the activity that is likely to be the predominant source or use of cash flow. ASU No. 2016-15 is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. The Company is still evaluating the impact of adopting ASU No. 2016-15 on its financial statements, but does not expect the adoption of ASU No. 2016-15 to have a material impact on its financial statements. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (“ASU No. 2016-18”). ASU No. 2016-18 requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, restricted cash and restricted cash equivalents. Therefore, amounts generally described as restricted cash should be included with cash and cash equivalents when reconciling the beginning of period and end of period total amounts shown on the statement of cash flows. ASU No. 2016-18 is effective for annual periods beginning after December 15, 2017, including interim periods within those fiscal years. The Company elected to early adopt ASU No. 2016-18 for the reporting period ending December 31, 2016 and was applied retrospectively. As a result of adoption of ASU No. 2016-18, the Company no longer presents the changes within restricted cash in the consolidated statements of cash flows. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business (“ASU No. 2017-01”) to add guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. ASU No. 2017-01 provides a screen to determine when an integrated set of assets and activities (collectively referred to as a “set”) is not a business. The screen requires that, when substantially all of the fair value of the gross assets acquired (or disposed of) is concentrated in a single identifiable asset or a group of similar identifiable assets, the set is not a business. If the screen is not met, ASU No. 2017-01 (1) requires that to be considered a business, a set must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output and (2) removes the evaluation of whether a market participant could replace missing elements. ASU No. 2017-01 provides a framework to assist entities in evaluating whether both an input and a substantive process are present. The framework includes two sets of criteria to consider that depend on whether a set has outputs. Although outputs are not required for a set to be a business, outputs generally are a key element of a business; therefore, the FASB has developed more stringent criteria for sets without outputs. ASU No. 2017-01 is effective for annual periods beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted. The amendments can be applied to transactions occurring before the guidance was issued (January 5, 2017) as long as the applicable financial statements have not been issued. The Company elected to early adopt ASU No. 2017-01 for the reporting period beginning January 1, 2017. As a result of the adoption of ASU No. 2017-01, the Company’s acquisitions of investment properties beginning January 1, 2017 could qualify as asset acquisitions (as opposed to business combinations). Transaction costs associated with asset acquisitions are capitalized, while transaction costs associated with business combinations will continue to be expensed as incurred.

REAL ESTATE HELD FOR INVESTME24

REAL ESTATE HELD FOR INVESTMENT (Tables)	9 Months Ended
	Sep. 30, 2017
Real Estate [Abstract]
Schedule of Real Estate Investments	The following table summarizes the Company’s real estate held for investment as of September 30, 2017 and December 31, 2016 , respectively (in thousands): September 30, 2017 December 31, 2016 Land $ 280,254 $ 312,623 Buildings and improvements 847,773 814,347 Tenant origination and absorption costs 49,210 46,557 Total real estate, cost 1,177,237 1,173,527 Accumulated depreciation and amortization (131,566 ) (113,429 ) Total real estate, net $ 1,045,671 $ 1,060,098 The following table provides summary information regarding the Company’s real estate held for investment as of September 30, 2017 (in thousands): Property Date City State Property Type Land Building Tenant Origination and Absorption Total Accumulated Depreciation and Amortization Total Ownership % Northridge Center I & II (1) 03/25/2011 Atlanta GA Office $ 2,234 $ 6,914 $ — $ 9,148 $ (2,584 ) $ 6,564 100.0 % Iron Point Business Park (1) 06/21/2011 Folsom CA Office 2,671 19,547 — 22,218 (5,648 ) 16,570 100.0 % Richardson Portfolio: Palisades Central I 11/23/2011 Richardson TX Office 1,037 10,278 — 11,315 (2,202 ) 9,113 90.0 % Palisades Central II 11/23/2011 Richardson TX Office 810 17,540 — 18,350 (4,111 ) 14,239 90.0 % Greenway I 11/23/2011 Richardson TX Office 561 2,309 — 2,870 (791 ) 2,079 90.0 % Greenway III 11/23/2011 Richardson TX Office 702 3,802 559 5,063 (1,736 ) 3,327 90.0 % Undeveloped Land 11/23/2011 Richardson TX Undeveloped Land 3,134 — — 3,134 — 3,134 90.0 % Total Richardson Portfolio 6,244 33,929 559 40,732 (8,840 ) 31,892 Park Highlands (2) 12/30/2011 North Las Vegas NV Undeveloped Land 33,594 — — 33,594 — 33,594 (2) Bellevue Technology (1) 07/31/2012 Bellevue WA Office 25,506 56,409 1,767 83,682 (10,418 ) 73,264 100.0 % Powers Ferry Landing (1) 09/24/2012 Atlanta GA Office 1,643 7,642 — 9,285 (2,505 ) 6,780 100.0 % 1800 West Loop (1) 12/04/2012 Houston TX Office 8,360 60,481 4,176 73,017 (14,100 ) 58,917 100.0 % West Loop I & II (1) 12/07/2012 Houston TX Office 7,300 32,867 1,662 41,829 (7,024 ) 34,805 100.0 % Burbank Collection 12/12/2012 Burbank CA Retail 4,175 12,551 725 17,451 (2,198 ) 15,253 90.0 % Austin Suburban Portfolio (3) 03/28/2013 Austin TX Office 8,288 69,478 836 78,602 (10,851 ) 67,751 100.0 % Westmoor Center (1) 06/12/2013 Westminster CO Office 10,058 73,283 5,083 88,424 (15,050 ) 73,374 100.0 % Central Building 07/10/2013 Seattle WA Office 7,015 27,055 1,428 35,498 (4,701 ) 30,797 100.0 % 1180 Raymond 08/20/2013 Newark NJ Apartment 8,292 38,049 — 46,341 (4,938 ) 41,403 100.0 % Park Highlands II 12/10/2013 North Las Vegas NV Undeveloped Land 24,692 — — 24,692 — 24,692 100.0 % Maitland Promenade II (1) 12/18/2013 Orlando FL Office 3,434 25,033 3,313 31,780 (5,492 ) 26,288 100.0 % Plaza Buildings (1) 01/14/2014 Bellevue WA Office 53,040 139,383 7,190 199,613 (23,723 ) 175,890 100.0 % 424 Bedford 01/31/2014 Brooklyn NY Apartment 8,860 25,615 — 34,475 (2,616 ) 31,859 90.0 % Richardson Land II 09/04/2014 Richardson TX Undeveloped Land 3,418 — — 3,418 — 3,418 90.0 % Westpark Portfolio 05/10/2016 Redmond WA Office/Flex/Industrial 36,085 88,125 7,663 131,873 (7,871 ) 124,002 100.0 % Crown Pointe 02/14/2017 Dunwoody GA Office 22,590 57,815 5,855 86,260 (2,807 ) 83,453 100.0 % 125 John Carpenter 09/15/2017 Irving TX Office 2,755 73,597 8,953 85,305 (200 ) 85,105 100.0 % $ 280,254 $ 847,773 $ 49,210 $ 1,177,237 $ (131,566 ) $ 1,045,671 _____________________ (1) On November 8, 2017 , the Company sold this property. See note 15 , “Subsequent Events - Singapore Transaction ” for more information. (2) On September 7, 2016, a subsidiary of the Company that owns a portion of Park Highlands, sold 820 units of 10% Class A non-voting preferred membership units for $0.8 million to accredited investors. The amount of the Class A non-voting preferred membership units raised, net of offering costs, is included in other liabilities on the accompanying consolidated balance sheets. (3) On November 8, 2017 , the Company sold two of the three office properties, Westech 360 and Great Hills Plaza. See note 15 , “Subsequent Events - Singapore Transaction ” for more information.
Schedule of Future Minimum Rental Income for Company's Properties	As of September 30, 2017 , the future minimum rental income from the Company’s properties, excluding apartment leases, under non-cancelable operating leases was as follows (in thousands): October 1, 2017 through December 31, 2017 $ 25,468 2018 99,939 2019 87,116 2020 71,983 2021 55,922 Thereafter 137,582 $ 478,010
Schedules of Concentration of Risk, by Risk Factor	As of September 30, 2017 , the Company’s commercial real estate properties were leased to approximately 600 tenants over a diverse range of industries and geographic areas. The Company’s highest tenant industry concentrations (greater than 10% of annualized base rent) were as follows: Industry Number of Tenants Annualized Base Rent (1) (in thousands) Percentage of Annualized Base Rent Insurance Carriers & Related Activities 35 $ 11,256 10.6 % Computer System Design & Programming 55 11,246 10.6 % $ 22,502 21.2 % _____________________ (1) Annualized base rent represents annualized contractual base rental income as of September 30, 2017 , adjusted to straight-line any contractual tenant concessions (including free rent), rent increases and rent decreases from the lease’s inception through the balance of the lease term.

TENANT ORIGINATION AND ABSORP25

TENANT ORIGINATION AND ABSORPTION COSTS, ABOVE-MARKET LEASE ASSETS AND BELOW-MARKET LEASE LIABILITIES (Tables)	9 Months Ended
	Sep. 30, 2017
Tenant Origination and Absorption Costs, Above-Market Lease Assets and Below-Market Lease Liabilities [Abstract]
Tenant Origination and Absorption Costs, Above-Market Lease Assets and Below-Market Lease Liabilities	As of September 30, 2017 and December 31, 2016 , the Company’s tenant origination and absorption costs, above-market lease assets and below-market lease liabilities (excluding fully amortized assets and liabilities and accumulated amortization) were as follows (in thousands): Tenant Origination and Absorption Costs Above-Market Lease Assets Below-Market Lease Liabilities September 30, 2017 December 31, 2016 September 30, 2017 December 31, 2016 September 30, 2017 December 31, 2016 Cost $ 49,210 $ 46,557 $ 1,330 $ 1,808 $ (6,015 ) $ (9,189 ) Accumulated Amortization (21,621 ) (22,327 ) (935 ) (1,190 ) 2,264 3,160 Net Amount $ 27,589 $ 24,230 $ 395 $ 618 $ (3,751 ) $ (6,029 )
Amortization of Tenant Origination and Absorption Costs, Above-Market Leases and Below-Market Lease Liabilities	Increases (decreases) in net income as a result of amortization of the Company’s tenant origination and absorption costs, above-market lease assets and below-market lease liabilities for the three and nine months ended September 30, 2017 and 2016 were as follows (in thousands): Tenant Origination and Absorption Costs Above-Market Lease Assets Below-Market Lease Liabilities For the Three Months Ended For the Three Months Ended For the Three Months Ended 2017 2016 2017 2016 2017 2016 Amortization $ (2,190 ) $ (3,068 ) $ (62 ) $ (119 ) $ 278 $ 1,045 Tenant Origination and Above-Market Below-Market For the Nine Months Ended For the Nine Months Ended For the Nine Months Ended 2017 2016 2017 2016 2017 2016 Amortization $ (8,268 ) $ (7,765 ) $ (229 ) $ (359 ) $ 2,482 $ 1,734

REAL ESTATE EQUITY SECURITIES (

REAL ESTATE EQUITY SECURITIES (Tables)	9 Months Ended
	Sep. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Schedule of Activity of Real Estate Securities	The following summarizes the activity related to real estate equity securities for the nine months ended September 30, 2017 (in thousands): Amortized Cost Basis Unrealized Gains Total Real estate equity securities - December 31, 2016 $ — $ — $ — Purchase of real estate equity securities 42,845 — 42,845 Acquisition fee to affiliate and purchase commission 463 — 463 Unrealized change in market value of real estate equity securities — 3,714 3,714 Real estate equity securities - September 30, 2017 $ 43,308 $ 3,714 $ 47,022

REAL ESTATE DEBT SECURITIES (Ta

REAL ESTATE DEBT SECURITIES (Tables)	9 Months Ended
	Sep. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Schedule of Activity of Real Estate Debt Securities	As of September 30, 2017 , the Company owned an investment in real estate debt securities. The Company’s investment in real estate debt securities is classified as held to maturity, as the Company has the intent and ability to hold its investment until maturity, and it is not more likely than not that the Company would be required to sell its investment before recovery of the Company’s amortized cost basis. The information for those real estate debt securities as of September 30, 2017 and December 31, 2016 is set forth below (in thousands): Debt Securities Name Dates Acquired Debt Securities Type Outstanding Principal Balance as of September 30, 2017 (1) Book Value as of September 30, 2017 (2) Book Value as of December 31, 2016 (2) Contractual Interest Rate (3) Annualized Effective Interest Rate (3) Maturity Date Battery Point Series B Preferred Units 10/28/2016 / 03/30/2017 / 05/12/2017 Series B Preferred Units $ 17,500 $ 17,642 $ 4,683 9.0 % 11.1 % 10/28/2019 _____________________ (1) Outstanding principal balance as of September 30, 2017 represents principal balance outstanding under the real estate debt securities. (2) Book value of the real estate debt securities represents outstanding principal balance adjusted for unamortized acquisition discounts, origination fees and direct origination and acquisition costs and additional interest accretion. (3) Contractual interest rate is the stated interest rate on the face of the real estate securities. Annualized effective interest rate is calculated as the actual interest income recognized in 2017 , using the interest method, annualized (if applicable) and divided by the average amortized cost basis of the investment. The annualized effective interest rate and contractual interest rate presented are as of September 30, 2017 . The following summarizes the activity related to real estate debt securities for the nine months ended September 30, 2017 (in thousands): Real estate debt securities - December 31, 2016 $ 4,683 Face value of additional real estate debt securities acquired 12,500 Deferred interest receivable and interest accretion 218 Closing costs 3 Accretion of commitment fee, net of closing costs 238 Real estate debt securities - September 30, 2017 $ 17,642
Schedule of Interest Income from Real Estate Debt Securities	For the three and nine months ended September 30, 2017 , interest income from real estate debt securities consisted of the following (in thousands): Three Months Ended Nine Months Ended September 30, 2017 September 30, 2017 Contractual interest income $ 403 $ 815 Interest accretion 97 218 Accretion of commitment fee, net of closing costs and acquisition fee 11 238 Interest income from real estate debt securities $ 511 $ 1,271

REAL ESTATE SALES (Tables)

REAL ESTATE SALES (Tables)	9 Months Ended
	Sep. 30, 2017
Discontinued Operations and Disposal Groups [Abstract]
Schedule of Assets and Liabilities of Real Estate Held-for-Sale	The following summary presents the major components of assets and liabilities related to real estate held for sale as of September 30, 2017 and December 31, 2016 (in thousands): September 30, 2017 December 31, 2016 Assets related to real estate held for sale Real estate, cost $ — $ 53,680 Accumulated depreciation and amortization — (6,747 ) Real estate, net — 46,933 Other assets — 1,488 Total assets related to real estate held for sale $ — $ 48,421 Liabilities related to real estate held for sale Notes payable, net — 31,450 Other liabilities — 522 Total liabilities related to real estate held for sale $ — $ 31,972
Schedule of Revenue and Expenses of Real Estate Held-for-Sale	The following table summarizes certain revenue and expenses related to this property for the three and nine months ended September 30, 2017 and 2016 (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 Revenues Rental income $ — $ 1,481 $ 2,287 $ 4,462 Tenant reimbursements and other operating income — 151 98 323 Total revenues $ — $ 1,632 $ 2,385 $ 4,785 Expenses Operating, maintenance, and management $ — $ 400 $ 714 $ 1,244 Real estate taxes and insurance — 269 475 864 Asset management fees to affiliate — 102 150 303 Depreciation and amortization — 593 604 1,808 Interest expense — 209 396 599 Total expenses $ — $ 1,573 $ 2,339 $ 4,818

NOTES AND BOND PAYABLE (Tables)

NOTES AND BOND PAYABLE (Tables)	9 Months Ended
	Sep. 30, 2017
Notes and Bonds Payable [Abstract]
Schedule of Long-term Debt Instruments	As of September 30, 2017 and December 31, 2016 , the Company’s notes and bonds payable, including notes payable related to real estate held for sale, consisted of the following (dollars in thousands): Book Value as of September 30, 2017 Book Value as of December 31, 2016 Contractual Interest Rate as of September 30, 2017 (1) Effective Interest Rate at September 30, 2017 (1) Payment Type Maturity (2) Richardson Portfolio Mortgage Loan $ 37,036 $ 40,594 One-Month LIBOR + 2.10% 3.34% Principal & Interest 05/01/2018 Bellevue Technology Center Mortgage Loan (3) 58,860 59,400 One-Month LIBOR + 2.25% 3.49% Principal & Interest 03/01/2019 Portfolio Revolving Loan Facility (4) 44,600 11,799 One-Month LIBOR + 2.75% 3.99% Principal & Interest 05/01/2019 Portfolio Mortgage Loan (5) 107,905 106,479 One-Month LIBOR + 2.25% 3.49% Principal & Interest 07/01/2018 Burbank Collection Mortgage Loan 9,591 9,812 One-Month LIBOR + 2.35% 3.60% Principal & Interest 09/30/2018 50 Congress Mortgage Loan (6) — 31,525 (6) (6) (6) (6) 1180 Raymond Bond Payable 6,505 6,635 6.50% 6.50% Principal & Interest 09/01/2036 Central Building Mortgage Loan 27,600 27,600 One-Month LIBOR + 1.75% 2.99% Interest Only 11/13/2018 Maitland Promenade II Mortgage Loan (3) 21,830 20,877 One-Month LIBOR + 2.90% 4.13% Principal & Interest 01/01/2018 Westmoor Center Mortgage Loan (3) 61,582 62,000 One-Month LIBOR + 2.25% 3.49% Principal & Interest 02/01/2018 Plaza Buildings Senior Loan (3) 108,886 109,866 One-Month LIBOR + 1.90% 3.14% Principal & Interest 01/14/2018 424 Bedford Mortgage Loan 24,422 24,832 3.91% 3.91% Principal & Interest 10/01/2022 1180 Raymond Mortgage Loan 31,000 31,000 One-Month LIBOR + 2.25% 3.49% Interest Only 12/01/2017 KBS SOR (BVI) Holdings, Ltd. Series A Debentures (7) 274,541 251,811 4.25% 4.25% (7) 03/01/2023 Westpark Portfolio Mortgage Loan 85,200 83,200 One-Month LIBOR + 2.50% 3.74% Interest Only (8) 07/01/2020 353 Sacramento Mortgage Loan (9) — 85,500 (9) (9) (9) (9) Crown Pointe Mortgage Loan 50,500 — One-Month LIBOR + 2.60% 3.84% Interest Only 02/13/2020 125 John Carpenter Mortgage Loan 50,130 — (10) 2.99% Interest Only 10/01/2022 Total Notes and Bonds Payable principal outstanding 1,000,188 962,930 Net Premium/(Discount) on Notes and Bonds Payable (11) 124 88 Deferred financing costs, net (10,064 ) (12,394 ) Total Notes and Bonds Payable, net $ 990,248 $ 950,624 _____________________ (1) Contractual interest rate represents the interest rate in effect under the loan as of September 30, 2017 . Effective interest rate is calculated as the actual interest rate in effect as of September 30, 2017 (consisting of the contractual interest rate and contractual floor rates), using interest rate indices at September 30, 2017 , where applicable. (2) Represents the initial maturity date or the maturity date as extended as of September 30, 2017 ; subject to certain conditions, the maturity dates of certain loans may be extended beyond the date shown. (3) On November 8, 2017 , in connection with the sale of property, the Company repaid the entire principal balance and all other sums due under this loan. See note 15 , “Subsequent Events - Singapore Transaction ” for more information. (4) The Portfolio Revolving Loan Facility is secured by the 1800 West Loop Building and the Iron Point Business Park. On May 1, 2017, the Company entered into a loan modification agreement to extend the maturity date of the Portfolio Revolving Loan Facility to May 1, 2019. As a result of this modification, the Portfolio Revolving Loan Facility bears interest at a floating rate of 2.75% over one-month LIBOR. The Portfolio Revolving Loan Facility is comprised of $30.0 million of revolving debt and $45.0 million of non-revolving debt available to be used for tenant improvements, leasing commissions and capital improvements, subject to certain terms and conditions contained in the loan documents. As of September 30, 2017 , $44.6 million of non-revolving debt had been disbursed to the Company and $29.8 million of revolving debt is available for future disbursements, subject to certain conditions contained in the loan documents. On November 8, 2017 , in connection with the sale of property, the Company repaid the entire principal balance and all other sums due under this loan. See note 15 , “Subsequent Events - Singapore Transaction ” for more information. (5) On November 8, 2017 , in connection with the sale of certain properties secured by this loan, the Company repaid all but $10.0 million principal balance. The Portfolio Mortgage Loan is now only secured by one office property in the Austin Suburban Portfolio, Park Centre. See note 15 , “Subsequent Events - Singapore Transaction ” for more information. (6) On May 15, 2017, in connection with the disposition of 50 Congress Street, the Company repaid the $31.4 million outstanding principal balance due under the 50 Congress Street Mortgage Loan. (7) See “ – Israeli Bond Financing” below. (8) Represents the payment type required under the loan as of September 30, 2017 . Certain future monthly payments due under this loan also include amortizing principal payments. For more information of the Company’s contractual obligations under its notes and bonds payable, see five-year maturity table below. (9) On July 6, 2017, in connection with the partial interest sale of 353 Sacramento, the 353 Sacramento Mortgage Loan was deconsolidated from the Company's balance sheet. See note 12 , “Investment in Unconsolidated Joint Ventures” for a further discussion on the Company’s partial sale of 353 Sacramento. (10) The 125 John Carpenter Mortgage Loan bears interest at a floating rate of the greater of (a) 2.0% or (b) 175 basis points over one-month LIBOR. (11) Represents the unamortized premium/discount on notes and bonds payable due to the above- and below-market interest rates when the debt was assumed. The discount/premium is amortized over the remaining life of the notes and bonds payable.
Schedule of Maturities of Long-term Debt	The following is a schedule of maturities, including principal amortization payments, for all notes and bonds payable outstanding as of September 30, 2017 (in thousands): October 1, 2017 through December 31, 2017 $ 32,706 2018 376,228 2019 158,157 2020 189,922 2021 55,787 Thereafter 187,388 $ 1,000,188

DERIVATIVE INSTRUMENTS (Tables)

DERIVATIVE INSTRUMENTS (Tables)	9 Months Ended
	Sep. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Interest Rate Derivatives	The following table summarizes the notional amount and other information related to the Company’s foreign currency collars as of December 31, 2016 . The notional amount is an indication of the extent of the Company’s involvement in each instrument at that time, but does not represent exposure to credit, interest rate or market risks (currency in thousands): Derivative Instruments Notional Amount Strike Price Trade Date Maturity Date Derivative instruments not designated as hedging instruments Foreign currency collar $ 100,000 3.72 - 3.83 ILS-USD 08/08/2016 08/08/2017 Foreign currency collar 50,000 3.67 - 3.77 ILS-USD 08/16/2016 08/16/2017 Foreign currency collar 50,000 3.68 - 3.78 ILS-USD 08/16/2016 08/16/2017 Foreign currency collar 50,000 3.67 - 3.77 ILS-USD 08/22/2016 08/22/2017 $ 250,000 The following table summarizes the notional amount and other information related to the Company’s derivative instrument as of September 30, 2017 . The notional amount is an indication of the extent of the Company’s involvement in the instrument at that time, but does not represent exposure to credit, interest rate or market risks (dollars in thousands): Derivative Instrument Effective Date Maturity Date Notional Value Reference Rate Interest rate cap 02/21/2017 02/13/2020 $ 46,875 One-month LIBOR at 3.00% The following table summarizes the notional amount and other information related to the Company’s foreign currency option as of September 30, 2017 . The notional amount is an indication of the extent of the Company’s involvement in each instrument at that time, but does not represent exposure to credit, interest rate or market risks (currency in thousands): Derivative Instrument Notional Amount Strike Price Trade Date Maturity Date Derivative instrument not designated as hedging instrument Foreign currency option $ 285,361 3.40 ILS-USD 08/03/2017 08/03/2018
Schedule of Derivative Instruments in Statement of Financial Position	The following table sets forth the fair value of the Company’s derivative instruments as well as their classification on the consolidated balance sheets as of September 30, 2017 and December 31, 2016 (dollars in thousands): September 30, 2017 December 31, 2016 Derivative Instruments Balance Sheet Location Number of Instruments Fair Value Number of Instruments Fair Value Derivative instruments not designated as hedging instruments Interest rate cap Prepaid expenses and other assets 1 $ 17 1 $ 12 Foreign currency collars Other liabilities — $ — 4 $ (3,910 ) Foreign currency option Prepaid expenses and other assets 1 $ 3,884 — $ —

FAIR VALUE DISCLOSURES (Tables)

FAIR VALUE DISCLOSURES (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Schedule of Face Value, Carrying Amounts and Fair Value	The following were the face values, carrying amounts and fair values of the Company’s financial instruments as of September 30, 2017 and December 31, 2016 , which carrying amounts do not approximate the fair values (in thousands): September 30, 2017 December 31, 2016 Face Value Carrying Amount Fair Value Face Value Carrying Amount Fair Value Financial asset: Real estate debt securities $ 17,500 $ 17,642 $ 17,358 $ 5,000 $ 4,683 $ 4,683 Financial liabilities: Notes and bond payable $ 725,647 $ 722,673 $ 727,521 $ 711,119 $ 707,169 $ 711,425 KBS SOR (BVI) Holdings, Ltd. Series A Debentures $ 274,541 $ 267,575 $ 288,817 $ 251,811 $ 243,455 $ 253,120
Fair Value, Assets Measured on Recurring Basis	As of September 30, 2017 , the Company measured the following assets at fair value (in thousands): Fair Value Measurements Using Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Recurring Basis: Real estate equity securities $ 47,022 $ 47,022 $ — $ — Asset derivatives - interest rate caps $ 17 $ — $ 17 $ — Asset derivative - foreign currency option $ 3,884 $ — $ 3,884 $ —

RELATED PARTY TRANSACTIONS (Tab

RELATED PARTY TRANSACTIONS (Tables)	9 Months Ended
	Sep. 30, 2017
Related Party Transactions [Abstract]
Schedule of Related Party Costs	Pursuant to the terms of these agreements, summarized below are the related-party costs incurred by the Company for the three and nine months ended September 30, 2017 and 2016 , respectively, and any related amounts payable as of September 30, 2017 and December 31, 2016 (in thousands): Incurred Payable as of Three Months Ended September 30, Nine Months Ended September 30, September 30, 2017 December 31, 2016 2017 2016 2017 2016 Expensed Asset management fees $ 2,800 $ 2,639 $ 8,404 6,932 $ — $ — Acquisition fees on real estate (1) — 1,690 — 2,964 — — Reimbursable operating expenses (2) 51 57 184 170 33 55 Disposition fees (3) — — 785 279 — — Capitalized Acquisition fees on real estate (1) 71 — 907 — — — Acquisition fees on real estate equity securities 43 — 429 — — — $ 2,965 $ 4,386 $ 10,709 $ 10,345 $ 33 $ 55 _____________________ (1) As a result of the adoption of ASU No. 2017-01, the Company’s acquisitions of real estate properties beginning January 1, 2017 generally qualify as an asset acquisition (as opposed to a business combination). Acquisition fees associated with asset acquisitions will be capitalized, while costs associated with business combinations will continue to be expensed as incurred. (2) The Advisor may seek reimbursement for certain employee costs under the Advisory Agreement. The Company has reimbursed the Advisor for the Company’s allocable portion of the salaries, benefits and overhead of internal audit department personnel providing services to the Company. These amounts totaled $49,000 and $168,000 for the three and nine months ended September 30, 2017 , respectively, and $30,000 and $114,000 for the three and nine months ended September 30, 2016 , respectively, and were the only employee costs reimbursed under the Advisory Agreement during these periods. The Company will not reimburse for employee costs in connection with services for which the Advisor earns acquisition, origination or disposition fees (other than reimbursement of travel and communication expenses) or for the salaries or benefits the Advisor or its affiliates may pay to the Company’s executive officers. In addition to the amounts above, the Company reimburses the Advisor for certain of the Company's direct costs incurred from third parties that were initially paid by the Advisor on behalf of the Company. (3) Disposition fees with respect to real estate sold are included in the gain on sale of real estate in the accompanying consolidated statements of operations. Disposition fees with respect to the assignment of the Company's real estate loan receivable are included in general and administrative expenses in the accompanying consolidated statements of operations.

INVESTMENT IN UNCONSOLIDATED 33

INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Tables)	9 Months Ended
	Sep. 30, 2017
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Investments in Unconsolidated Joint Ventures	Summarized financial information for the 110 William Joint Venture follows (in thousands): September 30, 2017 December 31, 2016 Assets: Real estate assets, net of accumulated depreciation and amortization $ 252,428 $ 262,192 Other assets 31,135 23,355 Total assets $ 283,563 $ 285,547 Liabilities and equity: Notes payable, net (1) $ 259,123 $ 157,628 Other liabilities 12,468 12,872 Partners’ capital 11,972 115,047 Total liabilities and equity $ 283,563 $ 285,547 _____________________ (1) See “- 110 William Joint Venture Refinance” below. Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 Revenues $ 9,614 $ 8,461 $ 27,328 $ 25,100 Expenses: Operating, maintenance, and management 2,577 3,162 7,343 8,120 Real estate taxes and insurance 1,637 1,535 4,725 4,502 Depreciation and amortization 4,664 3,563 12,277 9,831 Interest expense 3,951 1,517 9,150 4,541 Total expenses 12,829 9,777 33,495 26,994 Other income 14 16 42 48 Net loss $ (3,201 ) $ (1,300 ) $ (6,125 ) $ (1,846 ) Company’s equity in loss of unconsolidated joint venture $ (1,930 ) $ (791 ) $ (3,706 ) $ (1,139 ) Summarized financial information for the 353 Sacramento Joint Venture follows (in thousands): September 30, 2017 Assets: Real estate assets, net of accumulated depreciation and amortization $ 170,477 Other assets 5,438 Total assets $ 175,915 Liabilities and equity: Notes payable, net $ 87,605 Other liabilities 6,358 Partners’ capital 81,952 Total liabilities and equity $ 175,915 For the Period from July 6, 2017 to September 30, 2017 Revenues $ 3,507 Expenses: Operating, maintenance, and management 936 Real estate taxes and insurance 603 Depreciation and amortization 1,724 Interest expense 1,138 Total expenses 4,401 Net loss $ (894 ) Company’s equity in loss of unconsolidated joint venture $ (222 ) As of September 30, 2017 and December 31, 2016 , the Company’s investments in unconsolidated joint ventures were composed of the following (dollars in thousands): Investment Balance at Joint Venture Number of Properties Location Ownership % September 30, 2017 December 31, 2016 NIP Joint Venture 8 Various Less than 5.0% $ 4,317 $ 5,305 110 William Joint Venture 1 New York, New York 60.0% 8,668 70,544 353 Sacramento Joint Venture 1 San Francisco, California 55.0% 45,344 — $ 58,329 $ 75,849

SUPPLEMENTAL CASH FLOW AND SI34

SUPPLEMENTAL CASH FLOW AND SIGNIFICANT NONCASH TRANSACTION DISCLOSURES (Tables)	9 Months Ended
	Sep. 30, 2017
Supplemental Cash Flow and Significant Noncash Transaction Disclosures [Abstract]
Schedule of Cash Flow, Supplemental Disclosures	Supplemental cash flow and significant noncash transaction disclosures were as follows (in thousands): Nine Months Ended September 30, 2017 2016 Supplemental Disclosure of Cash Flow Information: Interest paid, net of capitalized interest of $1,732 and $1,478 for the nine months ended September 30, 2017 and 2016 , respectively $ 27,732 $ 16,146 Supplemental Disclosure of Significant Noncash Transactions: Assets and liabilities deconsolidated in connection with the 353 Sacramento partial sale: Real estate, net 170,586 — Rents and other receivables, net 1,244 — Prepaid expenses and other assets 555 — Notes payable, net 87,132 — Accounts payable and accrued liabilities 1,574 — Below-market leases, net 2,960 — Other liabilities 924 — Application of escrow deposits to acquisition of real estate 2,000 — Increase in accrued improvements to real estate 1,319 1,686 Distributions paid to common stockholders through common stock issuances pursuant to the dividend reinvestment plan 8,666 9,520

ORGANIZATION (Details)

ORGANIZATION (Details) $ in Thousands	Mar. 08, 2016USD ($)	Mar. 08, 2016ILS (₪)	Mar. 07, 2016ILS (₪)	Mar. 02, 2016ILS (₪)	Mar. 01, 2016ILS (₪)	Mar. 31, 2016USD ($)	Mar. 31, 2016ILS (₪)	Sep. 30, 2017USD ($)aportfoliopropertyinvestmentshares	Dec. 31, 2016USD ($)shares	Nov. 14, 2012USD ($)shares	Sep. 30, 2017USD ($)aportfoliopropertyinvestmentshares	Dec. 18, 2015shares	Oct. 23, 2012USD ($)shares	Dec. 29, 2011USD ($)shares	Jan. 08, 2009shares
Organizational Structure [Line Items]
Common stock, shares authorized (in shares)								1,000,000,000	1,000,000,000		1,000,000,000
Common stock, shares issued (in shares)								56,795,632	56,775,767		56,795,632		55,249	220,994
Partnership interest in Operating Partnership								0.10%
Partnership interest in the Operating Partnership and is its sole limited partner								99.90%
Issuance of common stock, value | $								$ 8,666	$ 12,616	$ 561,700
Shares of common stock sold under dividend reinvestment plan, value | $											$ 74,000
Redemptions of common stock, value | $								8,050	38,573		85,000
Common stock, value, issued | $								$ 568	$ 568		$ 568		$ 500	$ 2,000
Number of real estate properties | property								20			20
Number of investments in unconsolidated joint venture | investment								3			3
Number of investments in debt securities | investment								1			1
Number of investments in equity securities | investment								1			1
Office Properties
Organizational Structure [Line Items]
Number of real estate properties | property								11			11
Number of real estate properties acquired | property								9			9
Office Campus
Organizational Structure [Line Items]
Number of real estate properties | property								1			1
Office Portfolio
Organizational Structure [Line Items]
Number of real estate properties | portfolio								1			1
Number of real estate properties acquired | portfolio								1			1
Office Buildings, Portfolio
Organizational Structure [Line Items]
Number of real estate properties | property								4			4
Real estate area of undeveloped land | a								25			25
Office Property, Portfolio
Organizational Structure [Line Items]
Number of real estate properties | property								3			3
Number of real estate properties acquired | property								3			3
Office/Flex/Industrial Portfolio
Organizational Structure [Line Items]
Number of real estate properties | property								1			1
Office/Flex/Industrial Buildings
Organizational Structure [Line Items]
Number of real estate properties | property								21			21
Retail Properties
Organizational Structure [Line Items]
Number of real estate properties | property								1			1
Apartment Building
Organizational Structure [Line Items]
Number of real estate properties | property								2			2
Undeveloped Land
Organizational Structure [Line Items]
Real estate area of undeveloped land | a								1,100			1,100
Number of investments in real estate | investment								2			2
Series A Debentures | Bonds Payable
Organizational Structure [Line Items]
Maximum borrowing capacity | ₪				₪ 1,000,000,000
Contractual interest rate, percentage				4.25%
Proceeds from issuance of debt	$ 249,200	₪ 970,200,000	₪ 127,700,000		₪ 842,500,000	$ 249,200	₪ 970,200,000
Principal installment payments required as percent of total debt				20.00%
Maximum | Series A Debentures | Bonds Payable
Organizational Structure [Line Items]
Contractual interest rate, percentage				4.25%
Common Stock
Organizational Structure [Line Items]
Shares registered in primary offering															100,000,000
Shares registered for sale under dividend reinvestment plan															40,000,000
Issuance of common stock (in shares)								585,192	938,662	56,584,976
Issuance of common stock, value | $								$ 6	$ 9
Shares of common stock sold under dividend reinvestment plan, shares											6,620,362
Redemptions of common stock (in shares)								565,327	2,859,010		6,705,949
Redemptions of common stock, value | $								$ 6	$ 28
Common Stock | Minimum
Organizational Structure [Line Items]
Stock offering, shares authorized for issuance															250,000
Common Stock | Maximum
Organizational Structure [Line Items]
Stock offering, shares authorized for issuance															140,000,000
KBS Strategic Opportunity BVI
Organizational Structure [Line Items]
Common stock, shares authorized (in shares)												50,000
KBS Strategic Opportunity BVI | Operating Partnership
Organizational Structure [Line Items]
Common stock, shares issued (in shares)												10,000
KBS Capital Advisors LLC
Organizational Structure [Line Items]
Shares held by affiliate								20,000			20,000

SUMMARY OF SIGNIFICANT ACCOUN36

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Narrative) (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017$ / shares	Sep. 30, 2016$ / shares	Sep. 30, 2017segmentproperty$ / shares	Sep. 30, 2016$ / shares	Dec. 31, 2016property
Accounting Policies [Abstract]
Number of reportable segments | segment			1
Distributions declared per common share (in dollars per share) | $ / shares	$ 0.09452055	$ 0.0942623	$ 0.28047945	$ 0.2807377
Real Estate [Line Items]
Number of real estate properties disposed					0
Office Properties
Real Estate [Line Items]
Number of real estate properties disposed			1

SUMMARY OF SIGNIFICANT ACCOUN37

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Accounting Standards Updates) (Details)	12 Months Ended
	Dec. 31, 2016
Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other operating income and other ancillary income as percent of consolidated revenue	5.00%

SUMMARY OF SIGNIFICANT ACCOUN38

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Redeemable Common Stock) (Details) - USD ($) $ / shares in Units, $ in Thousands	Oct. 18, 2017	Sep. 14, 2017	Dec. 08, 2016	Oct. 23, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2016
Summary of Significant Accounting Policies [Line Items]
Redemption price percentage of most recent estimated value per share			95.00%
Redemption value					$ 1,000
Maximum percentage of weighted-average shares outstanding available for redemption during any calendar year					5.00%
Share redemption program, termination period					10 days
Other liabilities					$ 21,904			$ 18,095
Redeemable common stock payable					11,386			12,617
Remaining authorized repurchase amount					52,000
SOR Offer
Summary of Significant Accounting Policies [Line Items]
Stock repurchase program, number of shares authorized to be repurchased		3,553,660
Treasury stock acquired, cost per share		$ 14.07
Stock repurchase program, authorized amount		$ 50,000
Other liabilities					11,400
Remaining authorized repurchase amount					38,600
SOR Offer | Subsequent Event
Summary of Significant Accounting Policies [Line Items]
Stock repurchase program, number of shares authorized to be repurchased	1,135,912
Treasury stock acquired, cost per share	$ 14.07
Stock repurchase program, authorized amount	$ 16,000
Treasury stock, shares, acquired				4,688,671
Treasury stock, value, acquired				$ 66,000
Other Share Repurchases
Summary of Significant Accounting Policies [Line Items]
Remaining authorized repurchase amount					$ 4,700
Unfulfilled Redemption Request
Summary of Significant Accounting Policies [Line Items]
Other liabilities								$ 12,600
Forecast]
Summary of Significant Accounting Policies [Line Items]
Maximum number of shares redeemable per quarter, value						$ 3,000
Forecast] | SOR Offer
Summary of Significant Accounting Policies [Line Items]
Remaining authorized repurchase amount							$ 8,700

REAL ESTATE HELD FOR INVESTME39

REAL ESTATE HELD FOR INVESTMENT (Narrative) (Details) ft² in Millions	Sep. 30, 2017aft²portfoliounitpropertyinvestment
Real Estate Properties [Line Items]
Number of real estate properties	20
Rentable square feet | ft²	6
Percentage of portfolio occupied	83.00%
Office Properties
Real Estate Properties [Line Items]
Number of real estate properties	11
Number of real estate properties acquired	9
Office Campus
Real Estate Properties [Line Items]
Number of real estate properties	1
Office Portfolio
Real Estate Properties [Line Items]
Number of real estate properties | portfolio	1
Number of real estate properties acquired | portfolio	1
Office Buildings, Portfolio
Real Estate Properties [Line Items]
Number of real estate properties	4
Real estate area of undeveloped land | a	25
Office Property, Portfolio
Real Estate Properties [Line Items]
Number of real estate properties	3
Number of real estate properties acquired	3
Office/Flex/Industrial Buildings
Real Estate Properties [Line Items]
Number of real estate properties	21
Retail Properties
Real Estate Properties [Line Items]
Number of real estate properties	1
Apartment Building
Real Estate Properties [Line Items]
Number of real estate properties	2
Rentable square feet | ft²	0.3
Percentage of portfolio occupied	97.00%
Apartment Building | Multifamily Tower
Real Estate Properties [Line Items]
Number of units in real estate property | unit	383
Undeveloped Land
Real Estate Properties [Line Items]
Real estate area of undeveloped land | a	1,100
Number of investments in real estate | investment	2

REAL ESTATE HELD FOR INVESTME40

REAL ESTATE HELD FOR INVESTMENT (Schedule of Real Estate Investments) (Details) $ in Thousands	Nov. 08, 2017property	Sep. 07, 2016USD ($)unit	Sep. 30, 2017USD ($)property	Dec. 31, 2016USD ($)property
Real Estate Properties [Line Items]
Total real estate, cost			$ 1,177,237	$ 1,173,527
Accumulated depreciation and amortization			(131,566)	(113,429)
Total real estate, net			$ 1,045,671	$ 1,060,098
Number of real estate properties disposed | property				0
Number of real estate properties | property			20
Subsidiary of Common Parent
Real Estate Properties [Line Items]
Interest rate on Class A non-voting preferred membership units		10.00%
Proceeds from sale of units		$ 800
Subsidiary of Common Parent | Disposed of by Sale
Real Estate Properties [Line Items]
Number of real estate units | unit		820
Northridge Center I & II (1)
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Mar. 25, 2011
Total real estate, cost			$ 9,148
Accumulated depreciation and amortization			(2,584)
Total real estate, net			$ 6,564
Ownership %			100.00%
Iron Point Business Park (1)
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Jun. 21, 2011
Total real estate, cost			$ 22,218
Accumulated depreciation and amortization			(5,648)
Total real estate, net			$ 16,570
Ownership %			100.00%
Richardson Portfolio
Real Estate Properties [Line Items]
Total real estate, cost			$ 40,732
Accumulated depreciation and amortization			(8,840)
Total real estate, net			$ 31,892
Palisades Central I
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Nov. 23, 2011
Total real estate, cost			$ 11,315
Accumulated depreciation and amortization			(2,202)
Total real estate, net			$ 9,113
Ownership %			90.00%
Palisades Central II
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Nov. 23, 2011
Total real estate, cost			$ 18,350
Accumulated depreciation and amortization			(4,111)
Total real estate, net			$ 14,239
Ownership %			90.00%
Greenway I
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Nov. 23, 2011
Total real estate, cost			$ 2,870
Accumulated depreciation and amortization			(791)
Total real estate, net			$ 2,079
Ownership %			90.00%
Greenway III
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Nov. 23, 2011
Total real estate, cost			$ 5,063
Accumulated depreciation and amortization			(1,736)
Total real estate, net			$ 3,327
Ownership %			90.00%
Undeveloped Land
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Nov. 23, 2011
Total real estate, cost			$ 3,134
Accumulated depreciation and amortization			0
Total real estate, net			$ 3,134
Ownership %			90.00%
Park Highlands
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Dec. 30, 2011
Total real estate, cost			$ 33,594
Accumulated depreciation and amortization			0
Total real estate, net			$ 33,594
Bellevue Technology Center (1)
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Jul. 31, 2012
Total real estate, cost			$ 83,682
Accumulated depreciation and amortization			(10,418)
Total real estate, net			$ 73,264
Ownership %			100.00%
Powers Ferry Landing East (1)
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Sep. 24, 2012
Total real estate, cost			$ 9,285
Accumulated depreciation and amortization			(2,505)
Total real estate, net			$ 6,780
Ownership %			100.00%
1800 West Loop (1)
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Dec. 4, 2012
Total real estate, cost			$ 73,017
Accumulated depreciation and amortization			(14,100)
Total real estate, net			$ 58,917
Ownership %			100.00%
West Loop I & II (1)
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Dec. 7, 2012
Total real estate, cost			$ 41,829
Accumulated depreciation and amortization			(7,024)
Total real estate, net			$ 34,805
Ownership %			100.00%
Burbank Collection
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Dec. 12, 2012
Total real estate, cost			$ 17,451
Accumulated depreciation and amortization			(2,198)
Total real estate, net			$ 15,253
Ownership %			90.00%
Austin Suburban Portfolio (3)
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Mar. 28, 2013
Total real estate, cost			$ 78,602
Accumulated depreciation and amortization			(10,851)
Total real estate, net			$ 67,751
Ownership %			100.00%
Westmoor Center (1)
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Jun. 12, 2013
Total real estate, cost			$ 88,424
Accumulated depreciation and amortization			(15,050)
Total real estate, net			$ 73,374
Ownership %			100.00%
Central Building
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Jul. 10, 2013
Total real estate, cost			$ 35,498
Accumulated depreciation and amortization			(4,701)
Total real estate, net			$ 30,797
Ownership %			100.00%
1180 Raymond
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Aug. 20, 2013
Total real estate, cost			$ 46,341
Accumulated depreciation and amortization			(4,938)
Total real estate, net			$ 41,403
Ownership %			100.00%
Park Highlands II
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Dec. 10, 2013
Total real estate, cost			$ 24,692
Accumulated depreciation and amortization			0
Total real estate, net			$ 24,692
Ownership %			100.00%
Maitland Promenade II (1)
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Dec. 18, 2013
Total real estate, cost			$ 31,780
Accumulated depreciation and amortization			(5,492)
Total real estate, net			$ 26,288
Ownership %			100.00%
Plaza Buildings (1)
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Jan. 14, 2014
Total real estate, cost			$ 199,613
Accumulated depreciation and amortization			(23,723)
Total real estate, net			$ 175,890
Ownership %			100.00%
424 Bedford
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Jan. 31, 2014
Total real estate, cost			$ 34,475
Accumulated depreciation and amortization			(2,616)
Total real estate, net			$ 31,859
Ownership %			90.00%
Richardson Land II
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Sep. 4, 2014
Total real estate, cost			$ 3,418
Accumulated depreciation and amortization			0
Total real estate, net			$ 3,418
Ownership %			90.00%
Westpark Portfolio
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			May 10, 2016
Total real estate, cost			$ 131,873
Accumulated depreciation and amortization			(7,871)
Total real estate, net			$ 124,002
Ownership %			100.00%
Crown Pointe
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Feb. 14, 2017
Total real estate, cost			$ 86,260
Accumulated depreciation and amortization			(2,807)
Total real estate, net			$ 83,453
Ownership %			100.00%
125 John Carpenter
Real Estate Properties [Line Items]
Date Acquired or Foreclosed on			Sep. 15, 2017
Total real estate, cost			$ 85,305
Accumulated depreciation and amortization			(200)
Total real estate, net			$ 85,105
Ownership %			100.00%
Office Property, Portfolio
Real Estate Properties [Line Items]
Number of real estate properties | property			3
Office Property, Portfolio | Subsequent Event
Real Estate Properties [Line Items]
Number of real estate properties disposed | property	2
Land
Real Estate Properties [Line Items]
Total real estate, cost			$ 280,254	$ 312,623
Land | Northridge Center I & II (1)
Real Estate Properties [Line Items]
Total real estate, cost			2,234
Land | Iron Point Business Park (1)
Real Estate Properties [Line Items]
Total real estate, cost			2,671
Land | Richardson Portfolio
Real Estate Properties [Line Items]
Total real estate, cost			6,244
Land | Palisades Central I
Real Estate Properties [Line Items]
Total real estate, cost			1,037
Land | Palisades Central II
Real Estate Properties [Line Items]
Total real estate, cost			810
Land | Greenway I
Real Estate Properties [Line Items]
Total real estate, cost			561
Land | Greenway III
Real Estate Properties [Line Items]
Total real estate, cost			702
Land | Undeveloped Land
Real Estate Properties [Line Items]
Total real estate, cost			3,134
Land | Park Highlands
Real Estate Properties [Line Items]
Total real estate, cost			33,594
Land | Bellevue Technology Center (1)
Real Estate Properties [Line Items]
Total real estate, cost			25,506
Land | Powers Ferry Landing East (1)
Real Estate Properties [Line Items]
Total real estate, cost			1,643
Land | 1800 West Loop (1)
Real Estate Properties [Line Items]
Total real estate, cost			8,360
Land | West Loop I & II (1)
Real Estate Properties [Line Items]
Total real estate, cost			7,300
Land | Burbank Collection
Real Estate Properties [Line Items]
Total real estate, cost			4,175
Land | Austin Suburban Portfolio (3)
Real Estate Properties [Line Items]
Total real estate, cost			8,288
Land | Westmoor Center (1)
Real Estate Properties [Line Items]
Total real estate, cost			10,058
Land | Central Building
Real Estate Properties [Line Items]
Total real estate, cost			7,015
Land | 1180 Raymond
Real Estate Properties [Line Items]
Total real estate, cost			8,292
Land | Park Highlands II
Real Estate Properties [Line Items]
Total real estate, cost			24,692
Land | Maitland Promenade II (1)
Real Estate Properties [Line Items]
Total real estate, cost			3,434
Land | Plaza Buildings (1)
Real Estate Properties [Line Items]
Total real estate, cost			53,040
Land | 424 Bedford
Real Estate Properties [Line Items]
Total real estate, cost			8,860
Land | Richardson Land II
Real Estate Properties [Line Items]
Total real estate, cost			3,418
Land | Westpark Portfolio
Real Estate Properties [Line Items]
Total real estate, cost			36,085
Land | Crown Pointe
Real Estate Properties [Line Items]
Total real estate, cost			22,590
Land | 125 John Carpenter
Real Estate Properties [Line Items]
Total real estate, cost			2,755
Buildings and improvements
Real Estate Properties [Line Items]
Total real estate, cost			847,773	814,347
Buildings and improvements | Northridge Center I & II (1)
Real Estate Properties [Line Items]
Total real estate, cost			6,914
Buildings and improvements | Iron Point Business Park (1)
Real Estate Properties [Line Items]
Total real estate, cost			19,547
Buildings and improvements | Richardson Portfolio
Real Estate Properties [Line Items]
Total real estate, cost			33,929
Buildings and improvements | Palisades Central I
Real Estate Properties [Line Items]
Total real estate, cost			10,278
Buildings and improvements | Palisades Central II
Real Estate Properties [Line Items]
Total real estate, cost			17,540
Buildings and improvements | Greenway I
Real Estate Properties [Line Items]
Total real estate, cost			2,309
Buildings and improvements | Greenway III
Real Estate Properties [Line Items]
Total real estate, cost			3,802
Buildings and improvements | Undeveloped Land
Real Estate Properties [Line Items]
Total real estate, cost			0
Buildings and improvements | Park Highlands
Real Estate Properties [Line Items]
Total real estate, cost			0
Buildings and improvements | Bellevue Technology Center (1)
Real Estate Properties [Line Items]
Total real estate, cost			56,409
Buildings and improvements | Powers Ferry Landing East (1)
Real Estate Properties [Line Items]
Total real estate, cost			7,642
Buildings and improvements | 1800 West Loop (1)
Real Estate Properties [Line Items]
Total real estate, cost			60,481
Buildings and improvements | West Loop I & II (1)
Real Estate Properties [Line Items]
Total real estate, cost			32,867
Buildings and improvements | Burbank Collection
Real Estate Properties [Line Items]
Total real estate, cost			12,551
Buildings and improvements | Austin Suburban Portfolio (3)
Real Estate Properties [Line Items]
Total real estate, cost			69,478
Buildings and improvements | Westmoor Center (1)
Real Estate Properties [Line Items]
Total real estate, cost			73,283
Buildings and improvements | Central Building
Real Estate Properties [Line Items]
Total real estate, cost			27,055
Buildings and improvements | 1180 Raymond
Real Estate Properties [Line Items]
Total real estate, cost			38,049
Buildings and improvements | Park Highlands II
Real Estate Properties [Line Items]
Total real estate, cost			0
Buildings and improvements | Maitland Promenade II (1)
Real Estate Properties [Line Items]
Total real estate, cost			25,033
Buildings and improvements | Plaza Buildings (1)
Real Estate Properties [Line Items]
Total real estate, cost			139,383
Buildings and improvements | 424 Bedford
Real Estate Properties [Line Items]
Total real estate, cost			25,615
Buildings and improvements | Richardson Land II
Real Estate Properties [Line Items]
Total real estate, cost			0
Buildings and improvements | Westpark Portfolio
Real Estate Properties [Line Items]
Total real estate, cost			88,125
Buildings and improvements | Crown Pointe
Real Estate Properties [Line Items]
Total real estate, cost			57,815
Buildings and improvements | 125 John Carpenter
Real Estate Properties [Line Items]
Total real estate, cost			73,597
Tenant origination and absorption costs
Real Estate Properties [Line Items]
Total real estate, cost			49,210	$ 46,557
Tenant origination and absorption costs | Northridge Center I & II (1)
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Iron Point Business Park (1)
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Richardson Portfolio
Real Estate Properties [Line Items]
Total real estate, cost			559
Tenant origination and absorption costs | Palisades Central I
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Palisades Central II
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Greenway I
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Greenway III
Real Estate Properties [Line Items]
Total real estate, cost			559
Tenant origination and absorption costs | Undeveloped Land
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Park Highlands
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Bellevue Technology Center (1)
Real Estate Properties [Line Items]
Total real estate, cost			1,767
Tenant origination and absorption costs | Powers Ferry Landing East (1)
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | 1800 West Loop (1)
Real Estate Properties [Line Items]
Total real estate, cost			4,176
Tenant origination and absorption costs | West Loop I & II (1)
Real Estate Properties [Line Items]
Total real estate, cost			1,662
Tenant origination and absorption costs | Burbank Collection
Real Estate Properties [Line Items]
Total real estate, cost			725
Tenant origination and absorption costs | Austin Suburban Portfolio (3)
Real Estate Properties [Line Items]
Total real estate, cost			836
Tenant origination and absorption costs | Westmoor Center (1)
Real Estate Properties [Line Items]
Total real estate, cost			5,083
Tenant origination and absorption costs | Central Building
Real Estate Properties [Line Items]
Total real estate, cost			1,428
Tenant origination and absorption costs | 1180 Raymond
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Park Highlands II
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Maitland Promenade II (1)
Real Estate Properties [Line Items]
Total real estate, cost			3,313
Tenant origination and absorption costs | Plaza Buildings (1)
Real Estate Properties [Line Items]
Total real estate, cost			7,190
Tenant origination and absorption costs | 424 Bedford
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Richardson Land II
Real Estate Properties [Line Items]
Total real estate, cost			0
Tenant origination and absorption costs | Westpark Portfolio
Real Estate Properties [Line Items]
Total real estate, cost			7,663
Tenant origination and absorption costs | Crown Pointe
Real Estate Properties [Line Items]
Total real estate, cost			5,855
Tenant origination and absorption costs | 125 John Carpenter
Real Estate Properties [Line Items]
Total real estate, cost			$ 8,953

REAL ESTATE HELD FOR INVESTME41

REAL ESTATE HELD FOR INVESTMENT (Operating Leases) (Narrative) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2017USD ($)tenant	Sep. 30, 2016USD ($)	Dec. 31, 2016USD ($)
Operating Leased Assets [Line Items]
Recognition of deferred revenue, net of discontinued operations	$ 1.7	$ 2
Deferred rent receivables	27		$ 26.1
Incentive to Lessee	$ 3		3.2
Number of tenants | tenant	600
Other Liabilities
Operating Leased Assets [Line Items]
Security deposit liability	$ 7.3		$ 7.2
Maximum
Operating Leased Assets [Line Items]
Operating lease, term	14 years 8 months 12 days
Weighted Average
Operating Leased Assets [Line Items]
Operating lease, term	3 years 9 months 18 days
Apartment Building
Operating Leased Assets [Line Items]
Operating lease, term	1 year

REAL ESTATE HELD FOR INVESTME42

REAL ESTATE HELD FOR INVESTMENT (Future Minimum Rental Income) (Details) $ in Thousands	Sep. 30, 2017USD ($)
Real Estate [Abstract]
October 1, 2017 through December 31, 2017	$ 25,468
2,018	99,939
2,019	87,116
2,020	71,983
2,021	55,922
Thereafter	137,582
Future minimum rental income	$ 478,010

REAL ESTATE HELD FOR INVESTME43

REAL ESTATE HELD FOR INVESTMENT (Highest Tenant Industry Concentrations- Greater than 10% of Annual Base Rent) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)tenant
Concentration Risk [Line Items]
Number of tenants | tenant	600
Annualized Base Rent | $	$ 22,502
Percentage of Annualized Base Rent	21.20%
Insurance Carriers & Related Activities
Concentration Risk [Line Items]
Number of tenants | tenant	35
Annualized Base Rent | $	$ 11,256
Percentage of Annualized Base Rent	10.60%
Computer System Design & Programming
Concentration Risk [Line Items]
Number of tenants | tenant	55
Annualized Base Rent | $	$ 11,246
Percentage of Annualized Base Rent	10.60%

REAL ESTATE HELD FOR INVESTME44

REAL ESTATE HELD FOR INVESTMENT (Geographic Concentration Risk) (Details)	9 Months Ended
	Sep. 30, 2017
Concentration Risk [Line Items]
Concentration risk, percentage	21.20%
Washington | Assets, Total
Concentration Risk [Line Items]
Concentration risk, percentage	30.00%
Texas | Assets, Total
Concentration Risk [Line Items]
Concentration risk, percentage	21.00%

REAL ESTATE HELD FOR INVESTME45

REAL ESTATE HELD FOR INVESTMENT (Recent Real Estate Land Sale) (Details) $ in Thousands	Jul. 06, 2017USD ($)aft²	May 01, 2017USD ($)a	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of real estate, net			$ 2,239	$ 0	$ 36,267	$ 0
Gain on sale of real estate			$ 2,239	$ 0	$ 36,267	$ 0
Office Properties | 353 Sacramento
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership percentage	55.00%
Equity Method Investment, Ownership Percentage of Co-Investee	45.00%
Park Highlands | Undeveloped Land | Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land sold | a		102
Proceeds from sale of land		$ 17,400
Gain on sale of real estate, net		5,200
Deferred profit		2,600
Deferred gains on sales of real estate		1,700
Gain on sale of real estate		$ 5,200
353 Sacramento | Office Properties | Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of real estate, net	$ 1,700
Ownership percentage	45.00%
Net rentable area | ft²	284,751
Area of land | a	0.35
Sale price	$ 39,100
Gain on sale of real estate	$ 1,700

REAL ESTATE HELD FOR INVESTME46

REAL ESTATE HELD FOR INVESTMENT (Recent Acquisition) (Details) $ in Thousands	Sep. 15, 2017USD ($)ft²property	Feb. 14, 2017USD ($)ft²property	Sep. 30, 2017USD ($)ft²	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)ft²	Sep. 30, 2016USD ($)	Dec. 31, 2016USD ($)
Business Acquisition [Line Items]
Rentable square feet | ft²			6,000,000		6,000,000
Total real estate, cost			$ 1,177,237		$ 1,177,237		$ 1,173,527
Below-market leases			3,751		3,751		6,029
Revenues			36,414	$ 36,133	114,648	$ 98,365
Costs and expenses			47,383	$ 50,356	145,182	$ 119,176
Land
Business Acquisition [Line Items]
Total real estate, cost			280,254		280,254		312,623
Buildings and improvements
Business Acquisition [Line Items]
Total real estate, cost			847,773		847,773		814,347
Tenant origination and absorption costs
Business Acquisition [Line Items]
Total real estate, cost			49,210		49,210		$ 46,557
Office Properties | Crown Pointe
Business Acquisition [Line Items]
Number of real estate properties acquired | property		2
Rentable square feet | ft²		499,968
Purchase price		$ 83,100
Capitalized acquisition costs		$ 1,100
Below-market leases			1,000		1,000
Revenues			2,300		6,100
Costs and expenses			1,900		4,700
Office Properties | Crown Pointe | Tenant origination and absorption costs
Business Acquisition [Line Items]
Remaining amortization period		4 years 10 months 24 days
Office Properties | Crown Pointe | Below-market lease liabilities
Business Acquisition [Line Items]
Remaining amortization period		4 years 2 months 12 days
Office Properties | Crown Pointe | Land
Business Acquisition [Line Items]
Total real estate, cost			22,600		22,600
Office Properties | Crown Pointe | Buildings and improvements
Business Acquisition [Line Items]
Total real estate, cost			56,600		56,600
Office Properties | Crown Pointe | Tenant origination and absorption costs
Business Acquisition [Line Items]
Total real estate, cost			6,000		6,000
Office Properties | 125 John Carpenter
Business Acquisition [Line Items]
Number of real estate properties acquired | property	2
Rentable square feet | ft²	442,039
Purchase price	$ 82,800
Capitalized acquisition costs	500
Below-market leases	$ 2,100
Revenues			500		500
Costs and expenses			$ 300		$ 300
Office Properties | 125 John Carpenter | Tenant origination and absorption costs
Business Acquisition [Line Items]
Remaining amortization period	6 years 10 months 24 days
Office Properties | 125 John Carpenter | Below-market lease liabilities
Business Acquisition [Line Items]
Remaining amortization period	5 years 2 months 12 days
Office Properties | 125 John Carpenter | Land
Business Acquisition [Line Items]
Total real estate, cost	$ 2,700
Office Properties | 125 John Carpenter | Buildings and improvements
Business Acquisition [Line Items]
Total real estate, cost	73,600
Office Properties | 125 John Carpenter | Tenant origination and absorption costs
Business Acquisition [Line Items]
Total real estate, cost	$ 9,000

TENANT ORIGINATION AND ABSORP47

TENANT ORIGINATION AND ABSORPTION COSTS, ABOVE-MARKET LEASE ASSETS AND BELOW-MARKET LEASE LIABILITIES (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Tenant Origination and Absorption Costs, Above-Market Lease Assets and Below-Market Lease Liabilities [Abstract]
Tenant Origination And Absorption Costs, Cost	$ 49,210		$ 49,210		$ 46,557
Tenant Origination and Absorption Costs, Accumulated Amortization	(21,621)		(21,621)		(22,327)
Tenant Origination and Absorption Costs, Net Amount	27,589		27,589		24,230
Tenant Origination and Absorption Costs, Amortization	(2,190)	$ (3,068)	(8,268)	$ (7,765)
Above-Market Lease Assets, Cost	1,330		1,330		1,808
Above-Market Lease Assets, Accumulated Amortization	(935)		(935)		(1,190)
Above-Market Lease Assets, Net Amount	395		395		618
Above-Market Lease Assets, Amortization	(62)	(119)	(229)	(359)
Below-Market Lease Liabilities, Cost	(6,015)		(6,015)		(9,189)
Below-Market Lease Liabilities, Accumulated Amortization	2,264		2,264		3,160
Below-Market Lease Liabilities, Net Amount	(3,751)		(3,751)		$ (6,029)
Below-Market Lease Liabilities, Amortization	$ 278	$ 1,045	$ 2,482	$ 1,734

TENANT ORIGINATION AND ABSORP48

TENANT ORIGINATION AND ABSORPTION COSTS, ABOVE-MARKET LEASE ASSETS AND BELOW-MARKET LEASE LIABILITIES (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Tenant Origination and Absorption Costs, Above-Market Lease Assets and Below-Market Lease Liabilities [Line Items]
Tax abatement asset	$ 5,600		$ 5,600		$ 6,300
Depreciation and amortization	13,228	$ 14,337	43,136	$ 37,436
Property Tax Abatement Intangible Asset
Tenant Origination and Absorption Costs, Above-Market Lease Assets and Below-Market Lease Liabilities [Line Items]
Depreciation and amortization	$ 200	$ 200	$ 700	$ 700

REAL ESTATE EQUITY SECURITIES49

REAL ESTATE EQUITY SECURITIES (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Cost basis	$ 43,308		$ 43,308		$ 0
Investment fees			463
Dividend income from real estate equity securities	$ 1,015	$ 0	$ 1,505	$ 0
Whitestone REIT | Available-for-sale Securities
Schedule of Available-for-sale Securities [Line Items]
Shares purchased			3,603,189
KBS Capital Advisors LLC
Schedule of Available-for-sale Securities [Line Items]
Investment fees			$ 400

REAL ESTATE EQUITY SECURITIES50

REAL ESTATE EQUITY SECURITIES (Schedule of Activity of Real Estate Securities) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Available-for-sale Securities [Roll Forward]
Real estate securities, Amortized Cost Basis	$ 0
Real estate securities, Unrealized Gain	0
Real estate securities, Total	0
Purchase of real estate equity securities	42,845
Acquisition fee to affiliate and purchase commission	463
Unrealized change in market value of real estate equity securities	3,714
Real estate securities, Amortized Cost Basis	43,308
Real estate securities, Unrealized Gain	3,714
Real estate securities, Total	$ 47,022

REAL ESTATE DEBT SECURITIES (Sc

REAL ESTATE DEBT SECURITIES (Schedule of Investments in Debt Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Investment [Line Items]
Outstanding Principal Balance	$ 17,500	$ 5,000
Point Trust LLC | Series B Preferred Units
Investment [Line Items]
Outstanding Principal Balance	17,500
Book Value	$ 17,642	$ 4,683
Contractual Interest Rate	9.00%
Annualized Effective Interest Rate	11.10%

REAL ESTATE DEBT SECURITIES (52

REAL ESTATE DEBT SECURITIES (Schedule of Activity of Real Estate Securities) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Held-to-maturity Securities [Roll Forward]
Real estate debt securities - December 31, 2016	$ 5,000
Real estate debt securities - September 30, 2017	17,500
Debt Securities
Held-to-maturity Securities [Roll Forward]
Real estate debt securities - December 31, 2016	4,683
Face value of additional real estate debt securities acquired	12,500
Deferred interest receivable and interest accretion	218
Closing costs	3
Accretion of commitment fee, net of closing costs	238
Real estate debt securities - September 30, 2017	$ 17,642

REAL ESTATE DEBT SECURITIES (In

REAL ESTATE DEBT SECURITIES (Interest Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Investment [Line Items]
Contractual interest income	$ 340	$ 7	$ 536	$ 22
Debt Securities
Investment [Line Items]
Contractual interest income	403		815
Interest accretion	97		218
Accretion of commitment fee, net of closing costs and acquisition fee	11		238
Interest income from real estate debt securities	$ 511		$ 1,271

REAL ESTATE SALES (Narrative) (

REAL ESTATE SALES (Narrative) (Details) $ in Thousands	May 15, 2017USD ($)	Sep. 30, 2017USD ($)property	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)property	Sep. 30, 2016USD ($)	Dec. 31, 2016USD ($)property	Jul. 11, 2013ft²
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of real estate properties disposed | property						0
Proceeds from sales of real estate, net				$ 130,580	$ 0
Real estate held for investment, net		$ 1,045,671		1,045,671		$ 1,060,098
Accumulated depreciation and amortization		131,566		131,566		$ 113,429
Gain on sale of real estate, net		$ 2,239	$ 0	$ 36,267	$ 0
Office Properties
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of real estate properties disposed | property		1,000		1
Office Properties | 50 Congress Street | Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sales of real estate, net	$ 79,000
Proceeds from sales of real estate, net of concessions and credits	78,800
Real estate held for investment, net	47,700
Accumulated depreciation and amortization	5,900
Gain on sale of real estate, net	$ 29,400
Office Properties | 50 Congress Street
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net rentable area | ft²							179,872

REAL ESTATE SALES (Schedule of

REAL ESTATE SALES (Schedule of Major Components of Real Estate Held for Sale and Liabilities Related to Real Estate Held for Sale) (Details) - Held-for-sale - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate, cost	$ 0	$ 53,680
Accumulated depreciation and amortization	0	(6,747)
Real estate, net	0	46,933
Other assets	0	1,488
Total assets related to real estate held for sale	0	48,421
Notes payable, net	0	31,450
Other liabilities	0	522
Total liabilities related to real estate held for sale	$ 0	$ 31,972

REAL ESTATE SALES (Revenue and

REAL ESTATE SALES (Revenue and Expenses for Real Estate Held-for-Sale) (Details) - Disposed of by Sale - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues
Rental income	$ 0	$ 1,481	$ 2,287	$ 4,462
Tenant reimbursements and other operating income	0	151	98	323
Total revenues	0	1,632	2,385	4,785
Expenses
Operating, maintenance, and management	0	400	714	1,244
Real estate taxes and insurance	0	269	475	864
Asset management fees to affiliate	0	102	150	303
Depreciation and amortization	0	593	604	1,808
Interest expense	0	209	396	599
Total expenses	$ 0	$ 1,573	$ 2,339	$ 4,818

NOTES AND BOND PAYABLE (Schedul

NOTES AND BOND PAYABLE (Schedule of Long-term Debt Instruments) (Details) - USD ($)	Nov. 08, 2017	May 15, 2017	Mar. 06, 2017	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total Notes and Bonds Payable principal outstanding				$ 1,000,188,000	$ 962,930,000
Net Premium/(Discount) on Notes and Bonds Payable				124,000	88,000
Deferred financing costs, net				(10,064,000)	(12,394,000)
Total notes and bonds payable, net				990,248,000	950,624,000
Extinguishment of debt			$ 156,000,000
Mortgages | Richardson Portfolio Mortgage Loan
Debt Instrument [Line Items]
Notes payable				$ 37,036,000	40,594,000
Interest rate, effective percentage				3.34%
Mortgages | Richardson Portfolio Mortgage Loan | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				2.10%
Mortgages | Bellevue Technology Center Mortgage Loan (3)
Debt Instrument [Line Items]
Notes payable				$ 58,860,000	59,400,000
Interest rate, effective percentage				3.49%
Mortgages | Bellevue Technology Center Mortgage Loan (3) | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				2.25%
Mortgages | Portfolio Revolving Loan Facility
Debt Instrument [Line Items]
Notes payable				$ 44,600,000	11,799,000
Interest rate, effective percentage				3.99%
Mortgages | Portfolio Revolving Loan Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 30,000,000
Unused borrowing capacity, amount				29,800,000
Mortgages | Portfolio Revolving Loan Facility | Non-Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				45,000,000
Amount outstanding				$ 44,600,000
Mortgages | Portfolio Revolving Loan Facility | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				2.75%
Mortgages | Portfolio Mortgage Loan (5)
Debt Instrument [Line Items]
Notes payable				$ 107,905,000	106,479,000
Interest rate, effective percentage				3.49%
Mortgages | Portfolio Mortgage Loan (5) | Subsequent Event
Debt Instrument [Line Items]
Extinguishment of debt	$ 10,000,000
Mortgages | Portfolio Mortgage Loan (5) | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				2.25%
Mortgages | Burbank Collection Mortgage Loan
Debt Instrument [Line Items]
Notes payable				$ 9,591,000	9,812,000
Interest rate, effective percentage				3.60%
Mortgages | Burbank Collection Mortgage Loan | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				2.35%
Mortgages | 50 Congress Mortgage Loan
Debt Instrument [Line Items]
Notes payable				$ 0	31,525,000
Extinguishment of debt		$ 31,400,000
Mortgages | 1180 Raymond Bond Payable
Debt Instrument [Line Items]
Bonds payable				$ 6,505,000	6,635,000
Contractual interest rate, percentage				6.50%
Interest rate, effective percentage				6.50%
Mortgages | Central Building Mortgage Loan
Debt Instrument [Line Items]
Notes payable				$ 27,600,000	27,600,000
Interest rate, effective percentage				2.99%
Mortgages | Central Building Mortgage Loan | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				1.75%
Mortgages | Maitland Promenade II Mortgage Loan (3)
Debt Instrument [Line Items]
Notes payable				$ 21,830,000	20,877,000
Interest rate, effective percentage				4.13%
Mortgages | Maitland Promenade II Mortgage Loan (3) | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				2.90%
Mortgages | Westmoor Center Mortgage Loan (3)
Debt Instrument [Line Items]
Notes payable				$ 61,582,000	62,000,000
Interest rate, effective percentage				3.49%
Mortgages | Westmoor Center Mortgage Loan (3) | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				2.25%
Mortgages | Plaza Buildings Senior Loan (3)
Debt Instrument [Line Items]
Notes payable				$ 108,886,000	109,866,000
Interest rate, effective percentage				3.14%
Mortgages | Plaza Buildings Senior Loan (3) | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				1.90%
Mortgages | 424 Bedford Mortgage Loan
Debt Instrument [Line Items]
Notes payable				$ 24,422,000	24,832,000
Contractual interest rate, percentage				3.91%
Interest rate, effective percentage				3.91%
Mortgages | 1180 Raymond Mortgage Loan
Debt Instrument [Line Items]
Notes payable				$ 31,000,000	31,000,000
Interest rate, effective percentage				3.49%
Mortgages | 1180 Raymond Mortgage Loan | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				2.25%
Mortgages | KBS SOR (BVI) Holdings, Ltd. Series A Debentures
Debt Instrument [Line Items]
Notes payable				$ 274,541,000	251,811,000
Contractual interest rate, percentage				4.25%
Interest rate, effective percentage				4.25%
Interest rate during period				2.00%
Mortgages | Westpark Portfolio Mortgage Loan
Debt Instrument [Line Items]
Notes payable				$ 85,200,000	83,200,000
Interest rate, effective percentage				3.74%
Mortgages | Westpark Portfolio Mortgage Loan | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				2.50%
Mortgages | 353 Sacramento Mortgage Loan
Debt Instrument [Line Items]
Notes payable				$ 0	85,500,000
Mortgages | Crown Pointe Mortgage Loan
Debt Instrument [Line Items]
Notes payable				$ 50,500,000	0
Interest rate, effective percentage				3.84%
Mortgages | Crown Pointe Mortgage Loan | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				2.60%
Mortgages | 125 John Carpenter Mortgage Loan
Debt Instrument [Line Items]
Notes payable				$ 50,130,000	$ 0
Interest rate, effective percentage				2.99%
Mortgages | 125 John Carpenter Mortgage Loan | One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				1.75%

NOTES AND BOND PAYABLE (Narrati

NOTES AND BOND PAYABLE (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Debt Instrument [Line Items]
Interest expense	$ 9,618	$ 7,992	$ 29,327	$ 20,354
Amortization of deferred financing costs	1,000	1,100	3,578	2,908
Interest capitalized	600	$ 500	1,732	$ 1,478
Deferred finance costs	10,100		10,100		$ 12,500
Interest payable	$ 3,000		$ 3,000		5,300
Notes and Bonds Payable
Debt Instrument [Line Items]
Deferred finance costs					12,400
Prepaid Expenses and Other Current Assets
Debt Instrument [Line Items]
Deferred finance costs					$ 100

NOTES AND BOND PAYABLE (Sched59

NOTES AND BOND PAYABLE (Schedule of Maturities of Long-term Debt) (Details) $ in Thousands	Sep. 30, 2017USD ($)
Notes and Bonds Payable [Abstract]
October 1, 2017 through December 31, 2017	$ 32,706
2,018	376,228
2,019	158,157
2,020	189,922
2,021	55,787
Thereafter	187,388
Notes and bond payable outstanding	$ 1,000,188

NOTES AND BOND PAYABLE (Recent

NOTES AND BOND PAYABLE (Recent Bond Financing) (Details)	Mar. 08, 2016USD ($)	Mar. 08, 2016ILS (₪)	Mar. 07, 2016ILS (₪)	Mar. 02, 2016ILS (₪)	Mar. 01, 2016ILS (₪)	Mar. 31, 2016USD ($)	Mar. 31, 2016ILS (₪)	Sep. 30, 2017USD ($)instrument
Foreign currency option | Derivative instruments not designated as hedging instruments
Debt Instrument [Line Items]
Number of Instruments | instrument								1
Notional amount | $								$ 285,361,000
Bonds Payable | Series A Debentures
Debt Instrument [Line Items]
Maximum borrowing capacity | ₪				₪ 1,000,000,000
Interest rate during period						4.25%	4.25%
Proceeds from issuance of debt	$ 249,200,000	₪ 970,200,000	₪ 127,700,000		₪ 842,500,000	$ 249,200,000	₪ 970,200,000
Principal installment payments required as percent of total debt				20.00%
Bonds Payable | Series A Debentures | Maximum
Debt Instrument [Line Items]
Interest rate during period				4.25%

DERIVATIVE INSTRUMENTS (Notiona

DERIVATIVE INSTRUMENTS (Notional Amount) (Details) ₪ in Millions	Aug. 03, 2017USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Aug. 03, 2017ILS (₪)
Derivative [Line Items]
Purchase of interest rate cap		$ 107,000	$ 0
Derivative instruments not designated as hedging instruments | Foreign currency collars
Derivative [Line Items]
Notional Amount		250,000,000		₪ 970.2
Strike Price				3.4
Proceeds from derivatives	$ 6,600,000
Purchase of interest rate cap	$ 3,400,000
Derivative instruments not designated as hedging instruments | Foreign currency collar 1
Derivative [Line Items]
Notional Amount		$ 100,000,000
Derivative instruments not designated as hedging instruments | Foreign currency collar 1 | Minimum
Derivative [Line Items]
Strike Price		3.72
Derivative instruments not designated as hedging instruments | Foreign currency collar 1 | Maximum
Derivative [Line Items]
Strike Price		3.83
Derivative instruments not designated as hedging instruments | Foreign currency collar 2
Derivative [Line Items]
Notional Amount		$ 50,000,000
Derivative instruments not designated as hedging instruments | Foreign currency collar 2 | Minimum
Derivative [Line Items]
Strike Price		3.67
Derivative instruments not designated as hedging instruments | Foreign currency collar 2 | Maximum
Derivative [Line Items]
Strike Price		3.77
Derivative instruments not designated as hedging instruments | Foreign currency collar 3
Derivative [Line Items]
Notional Amount		$ 50,000,000
Derivative instruments not designated as hedging instruments | Foreign currency collar 3 | Minimum
Derivative [Line Items]
Strike Price		3.68
Derivative instruments not designated as hedging instruments | Foreign currency collar 3 | Maximum
Derivative [Line Items]
Strike Price		3.78
Derivative instruments not designated as hedging instruments | Foreign currency collar 4
Derivative [Line Items]
Notional Amount		$ 50,000,000
Derivative instruments not designated as hedging instruments | Foreign currency collar 4 | Minimum
Derivative [Line Items]
Strike Price		3.67
Derivative instruments not designated as hedging instruments | Foreign currency collar 4 | Maximum
Derivative [Line Items]
Strike Price		3.77
Derivative instruments not designated as hedging instruments | Foreign currency option
Derivative [Line Items]
Notional Amount		$ 285,361,000
Strike Price		3.40

DERIVATIVE INSTRUMENTS (Balance

DERIVATIVE INSTRUMENTS (Balance Sheets) (Details) ₪ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017USD ($)instrument	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)instrument	Sep. 30, 2016USD ($)	Aug. 03, 2017ILS (₪)	Dec. 31, 2016USD ($)instrument
Interest Rate Cap
Derivative [Line Items]
Unrealized loss on derivatives	$ 14,000	$ 8,200,000	$ 102,000	$ 6,100,000
Interest Rate Cap | Derivative instruments not designated as hedging instruments | Prepaid expenses and other assets
Derivative [Line Items]
Number of Instruments | instrument	1		1			1
Derivative Asset	$ 17,000		$ 17,000			$ 12,000
Interest Rate Cap | One-month LIBOR
Derivative [Line Items]
Reference Rate	3.00%		3.00%
Interest Rate Cap 1
Derivative [Line Items]
Maturity Date			Feb. 13, 2020
Notional Amount	$ 46,875,000		$ 46,875,000
Interest Rate Cap 1 | One-month LIBOR
Derivative [Line Items]
Reference Rate	3.00%		3.00%
Foreign currency collars
Derivative [Line Items]
Gain (loss) recognized on derivatives	$ (8,100,000)		$ 10,900,000
Foreign currency transaction gain (loss)	3,700,000	$ (1,500,000)	(22,400,000)	$ 1,500,000
Foreign currency collars | Derivative instruments not designated as hedging instruments
Derivative [Line Items]
Notional Amount	$ 250,000,000		$ 250,000,000		₪ 970.2
Foreign currency collars | Derivative instruments not designated as hedging instruments | Other Liabilities
Derivative [Line Items]
Number of Instruments | instrument	0		0			4
Derivative Liability	$ 0		$ 0			$ (3,910,000)
Foreign currency option | Derivative instruments not designated as hedging instruments
Derivative [Line Items]
Notional Amount	$ 285,361,000		$ 285,361,000
Number of Instruments | instrument	1		1
Foreign currency option | Derivative instruments not designated as hedging instruments | Prepaid expenses and other assets
Derivative [Line Items]
Number of Instruments | instrument	1		1			0
Derivative Asset	$ 3,884,000		$ 3,884,000			$ 0

FAIR VALUE DISCLOSURES (Schedul

FAIR VALUE DISCLOSURES (Schedule of Face Value, Carrying Amounts and Fair Value) (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Real estate debt securities, Face Value	$ 17,500,000	$ 5,000,000
Notes and bond payable, Face Value	725,647,000	711,119,000
Series A Debentures
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes and bond payable, Face Value	274,541,000	251,811,000
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Real estate debt securities, Value	17,642,000	4,683,000
Notes and bond payable, Value	722,673,000	707,169,000
Carrying Amount | Series A Debentures
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes and bond payable, Value	267,575,000	243,455,000
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Real estate debt securities, Value	17,358,000	4,683,000
Notes and bond payable, Value	727,521,000	711,425,000
Fair Value | Series A Debentures
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes and bond payable, Value	$ 288,817,000	$ 253,120,000

FAIR VALUE DISCLOSURES (Sched64

FAIR VALUE DISCLOSURES (Schedule of Assets and Liabilities at Fair Value) (Details) - Recurring Basis $ in Thousands	Sep. 30, 2017USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate equity securities	$ 47,022
Asset derivatives - interest rate caps	17
Asset derivative - foreign currency forward hedge	3,884
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate equity securities	47,022
Asset derivatives - interest rate caps	0
Asset derivative - foreign currency forward hedge	0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate equity securities	0
Asset derivatives - interest rate caps	17
Asset derivative - foreign currency forward hedge	3,884
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate equity securities	0
Asset derivatives - interest rate caps	0
Asset derivative - foreign currency forward hedge	$ 0

RELATED PARTY TRANSACTIONS (Det

RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	Jul. 06, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Jul. 31, 2016
Related Party Transaction [Line Items]
Payable as of		$ 33		$ 33		$ 55
Payment for administrative fees		49	$ 30	168	$ 114
Advisor and Dealer Manager
Related Party Transaction [Line Items]
Incurred		2,965	4,386	10,709	10,345
Payable as of		33		33		55
Advisor and Dealer Manager | Asset management fees
Related Party Transaction [Line Items]
Expenses		2,800	2,639	8,404	6,932
Payable as of		0		0		0
Advisor and Dealer Manager | Acquisition fees on real estate
Related Party Transaction [Line Items]
Expenses		0	1,690	0	2,964
Incurred		71	0	907	0
Payable as of		0		0		0
Advisor and Dealer Manager | Reimbursable operating expenses
Related Party Transaction [Line Items]
Expenses		51	57	184	170
Payable as of		33		33		55
Advisor and Dealer Manager | Disposition fees
Related Party Transaction [Line Items]
Expenses		0	0	785	279
Payable as of		0		0		0
Advisor and Dealer Manager | Acquisition fees on real estate equity securities
Related Party Transaction [Line Items]
Incurred		43	$ 0	429	0
Payable as of		0		0		$ 0
KBS Capital Advisors LLC | 353 Sacramento
Related Party Transaction [Line Items]
Acquisition fees waved, percent							45.00%
KBS Capital Advisors LLC | 125 John Carpenter
Related Party Transaction [Line Items]
Acquisition fees waved, amount				800
KBS Capital Advisors LLC | Legal and professional fees reimbursement
Related Party Transaction [Line Items]
Incurred				400	100
KBS Capital Advisors LLC | Property insurance rebate
Related Party Transaction [Line Items]
Incurred					$ 100
Due from related parties		$ 100		$ 100
Immediate Family Member | Monarch Global Partners, LLC
Related Party Transaction [Line Items]
Payment for administrative fees	$ 100

INVESTMENT IN UNCONSOLIDATED 66

INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Investments in Unconsolidated Joint Ventures) (Details) $ in Thousands	Sep. 30, 2017USD ($)property	Dec. 31, 2016USD ($)
Schedule of Equity Method Investments [Line Items]
Number of Properties | property	20
Investment Balance	$ 58,329	$ 75,849
NIP Joint Venture
Schedule of Equity Method Investments [Line Items]
Investment Balance	$ 4,317	5,305
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%
Investment Balance	$ 8,668	70,544
353 Sacramento Joint Venture
Schedule of Equity Method Investments [Line Items]
Number of Properties | property	1
Ownership %	55.00%
Investment Balance	$ 45,344	$ 0

INVESTMENT IN UNCONSOLIDATED 67

INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Narrative) (Details) $ in Thousands	May 18, 2012USD ($)	Sep. 30, 2017USD ($)ft²property	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)ft²property	Sep. 30, 2016USD ($)	Jul. 06, 2017	Dec. 31, 2016USD ($)	May 02, 2014ft²
Schedule of Equity Method Investments [Line Items]
Number of real estate properties | property		20		20
Rentable square feet | ft²		6,000,000		6,000,000
Initial capital contribution				$ 0	$ 2,820
Investments in unconsolidated joint ventures		$ 58,329		58,329			$ 75,849
Income from unconsolidated joint venture		0	$ 0	1,869	0
Acquisition related costs		$ 0	274	0	542
Joint Venture
Schedule of Equity Method Investments [Line Items]
Ownership interest						55.00%
110 William JV Partner
Schedule of Equity Method Investments [Line Items]
Return of capital				58,200
Capital distribution				$ 38,800
Migdal Members
Schedule of Equity Method Investments [Line Items]
Ownership interest						45.00%
Office Properties
Schedule of Equity Method Investments [Line Items]
Number of real estate properties | property		11		11
Office Properties | 353 Sacramento | Disposed of by Sale
Schedule of Equity Method Investments [Line Items]
Ownership interest						45.00%
NIP Joint Venture
Schedule of Equity Method Investments [Line Items]
Initial capital contribution	$ 8,000
Investments in unconsolidated joint ventures		$ 4,317		$ 4,317			5,305
Distributions		$ 0	$ 0	2,900	$ 0
Income from unconsolidated joint venture				1,900
Return of capital				$ 1,000
NIP Joint Venture | Maximum
Schedule of Equity Method Investments [Line Items]
Ownership interest		5.00%		5.00%
NIP Joint Venture | Industrial
Schedule of Equity Method Investments [Line Items]
Number of real estate properties | property		8		8
Rentable square feet | ft²		4,400,000		4,400,000
110 William Joint Venture
Schedule of Equity Method Investments [Line Items]
Number of real estate properties | property		1		1
Rentable square feet | ft²								928,157
Ownership interest		60.00%		60.00%
Investments in unconsolidated joint ventures		$ 8,668		$ 8,668			70,544
Area of land | ft²								0.8
Acquisition related costs				$ 1,500
110 William Joint Venture | 110 William JV Partner
Schedule of Equity Method Investments [Line Items]
Ownership interest								60.00%
Noncontrolling interest								40.00%
353 Sacramento Joint Venture
Schedule of Equity Method Investments [Line Items]
Number of real estate properties | property		1		1
Ownership interest		55.00%		55.00%
Investments in unconsolidated joint ventures		$ 45,344		$ 45,344			$ 0

INVESTMENT IN UNCONSOLIDATED 68

INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (110 William Joint Venture Refinance) (Details)	Mar. 06, 2017USD ($)extensioninstrument	Sep. 30, 2017USD ($)	Dec. 31, 2016USD ($)	May 02, 2014USD ($)
Schedule of Equity Method Investments [Line Items]
Face amount		$ 725,647,000	$ 711,119,000
Extinguishment of debt	$ 156,000,000
One-month LIBOR | Interest Rate Cap
Schedule of Equity Method Investments [Line Items]
Reference Rate		3.00%
110 William Street Existing Loans | Mortgages
Schedule of Equity Method Investments [Line Items]
Face amount				$ 141,500,000
110 William Street Existing Loans | Mezzanine Loan
Schedule of Equity Method Investments [Line Items]
Face amount				$ 20,000,000
Refinancing Loans | Interest Rate Cap
Schedule of Equity Method Investments [Line Items]
Notional amount	275,000,000
Refinancing Loans | Interest Rate Cap | Maximum
Schedule of Equity Method Investments [Line Items]
Notional amount	$ 300,000,000
Refinancing Loans | One-month LIBOR | Interest Rate Cap
Schedule of Equity Method Investments [Line Items]
Number of instruments | instrument	3
Reference Rate	3.00%
Refinancing Loans | Mortgages
Schedule of Equity Method Investments [Line Items]
Number of extensions | extension	3
Extension period	1 year
110 William Street Mortgage Loan | Mortgages
Schedule of Equity Method Investments [Line Items]
Face amount	$ 232,300,000
Amount outstanding	205,000,000
Unused borrowing capacity, amount	$ 27,300,000
110 William Street Mortgage Loan | Mortgages | One-month LIBOR
Schedule of Equity Method Investments [Line Items]
Basis spread on variable rate	2.2472%
110 William Street Senior Mezzanine Loan | Mezzanine Loan
Schedule of Equity Method Investments [Line Items]
Face amount	$ 33,800,000
Amount outstanding	29,850,000
Unused borrowing capacity, amount	$ 4,000,000
110 William Street Senior Mezzanine Loan | Mezzanine Loan | One-month LIBOR
Schedule of Equity Method Investments [Line Items]
Basis spread on variable rate	6.25%
110 William Street Junior Mezzanine Loan | Mezzanine Loan
Schedule of Equity Method Investments [Line Items]
Face amount	$ 33,800,000
Amount outstanding	29,850,000
Unused borrowing capacity, amount	$ 4,000,000

INVESTMENT IN UNCONSOLIDATED 69

INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Summarized Financial Information - 110 William Joint Venture) (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Balance Sheet Related Disclosures [Abstract]
Real estate assets, net of accumulated depreciation and amortization	$ 1,045,671	$ 1,045,671		$ 1,045,671		$ 1,060,098
Total assets	1,344,353	1,344,353		1,344,353		1,310,116
Other liabilities	21,904	21,904		21,904		18,095
Total liabilities and equity	1,344,353	1,344,353		1,344,353		1,310,116
Income Statement [Abstract]
Revenues		36,414	$ 36,133	114,648	$ 98,365
Operating, maintenance, and management		11,431	10,932	33,638	29,755
Real estate taxes and insurance		4,780	4,516	14,932	12,419
Depreciation and amortization		13,228	14,337	43,136	37,436
Interest expense		9,618	7,992	29,327	20,354
Total expenses		47,383	50,356	145,182	119,176
Net (loss) income attributable to common stockholders		(10,534)	(14,951)	4,220	(21,804)
Company’s equity in loss of unconsolidated joint venture		(2,152)	(791)	(3,928)	(1,139)
110 William Joint Venture
Balance Sheet Related Disclosures [Abstract]
Real estate assets, net of accumulated depreciation and amortization	252,428	252,428		252,428		262,192
Other assets	31,135	31,135		31,135		23,355
Total assets	283,563	283,563		283,563		285,547
Notes payable, net	259,123	259,123		259,123		157,628
Other liabilities	12,468	12,468		12,468		12,872
Partners’ capital	11,972	11,972		11,972		115,047
Total liabilities and equity	283,563	283,563		283,563		$ 285,547
Income Statement [Abstract]
Revenues		9,614	8,461	27,328	25,100
Operating, maintenance, and management		2,577	3,162	7,343	8,120
Real estate taxes and insurance		1,637	1,535	4,725	4,502
Depreciation and amortization		4,664	3,563	12,277	9,831
Interest expense		3,951	1,517	9,150	4,541
Total expenses		12,829	9,777	33,495	26,994
Other income		14	16	42	48
Net (loss) income attributable to common stockholders		(3,201)	(1,300)	(6,125)	(1,846)
Company’s equity in loss of unconsolidated joint venture		(1,930)	$ (791)	(3,706)	$ (1,139)
353 Sacramento Joint Venture
Balance Sheet Related Disclosures [Abstract]
Real estate assets, net of accumulated depreciation and amortization	170,477	170,477		170,477
Other assets	5,438	5,438		5,438
Total assets	175,915	175,915		175,915
Notes payable, net	87,605	87,605		87,605
Other liabilities	6,358	6,358		6,358
Partners’ capital	81,952	81,952		81,952
Total liabilities and equity	175,915	$ 175,915		$ 175,915
Income Statement [Abstract]
Revenues	3,507
Operating, maintenance, and management	936
Real estate taxes and insurance	603
Depreciation and amortization	1,724
Interest expense	1,138
Total expenses	4,401
Net (loss) income attributable to common stockholders	(894)
Company’s equity in loss of unconsolidated joint venture	$ (222)

SUPPLEMENTAL CASH FLOW AND SI70

SUPPLEMENTAL CASH FLOW AND SIGNIFICANT NONCASH TRANSACTION DISCLOSURES (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Supplemental Disclosure of Cash Flow Information:
Interest paid, net of capitalized interest of $1,732 and $1,478 for the nine months ended September 30, 2017 and 2016, respectively			$ 27,732	$ 16,146
Interest capitalized	$ 600	$ 500	1,732	1,478
Assets and liabilities deconsolidated in connection with the 353 Sacramento partial sale:
Real estate, net	1,045,671		1,045,671		$ 1,060,098
Rents and other receivables, net	30,252		30,252		27,521
Prepaid expenses and other assets	31,469		31,469		28,476
Accounts payable and accrued liabilities	27,473		27,473		26,624
Below-market leases, net	3,751		3,751		6,029
Other liabilities	21,904		21,904		18,095
Application of escrow deposits to acquisition of real estate			2,000	0
Increase in accrued improvements to real estate			1,319	1,686
Distributions paid to common stockholders through common stock issuances pursuant to the dividend reinvestment plan			8,666	$ 9,520
353 Sacramento
Assets and liabilities deconsolidated in connection with the 353 Sacramento partial sale:
Real estate, net	170,586		170,586		0
Rents and other receivables, net	1,244		1,244		0
Prepaid expenses and other assets	555		555		0
Notes payable, net	87,132		87,132		0
Accounts payable and accrued liabilities	1,574		1,574		0
Below-market leases, net	2,960		2,960		0
Other liabilities	$ 924		$ 924		$ 0

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) $ in Thousands	Nov. 08, 2017USD ($)propertysubsidiary	Mar. 06, 2017USD ($)	Dec. 31, 2016USD ($)property	Sep. 30, 2017USD ($)
Subsequent Event [Line Items]
Number of real estate properties disposed | property			0
Real estate held for sale, net			$ 46,933	$ 0
Extinguishment of debt		$ 156,000
Singapore Portfolio
Subsequent Event [Line Items]
Real estate held for sale, net				$ 546,500
Subsequent Event | SREIT
Subsequent Event [Line Items]
Payments to acquire investments	$ 52,500
Interests acquired	9.50%
Subsequent Event | Secured Debt
Subsequent Event [Line Items]
Extinguishment of debt	$ 401,700
Subsequent Event | Singapore Portfolio
Subsequent Event [Line Items]
Number of wholly owned subsidiaries | subsidiary	11
Number of real estate properties disposed | property	11
Sale price	$ 804,000
Closing costs	$ 7,700