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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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

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Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

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Number of new stock issued during the period.

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Value of stock issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the holder of the stock to reinvest dividends paid to them by the entity on new issues of stock by the entity.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Number of stock bought back by the entity at the exercise price or redemption price.

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Equity impact of the value of stock bought back by the entity at the exercise price or redemption price.

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ORGANIZATION (Details) $ / shares in Units, $ in Millions		3 Months Ended	55 Months Ended	156 Months Ended
ORGANIZATION (Details) $ / shares in Units, $ in Millions	Oct. 03, 2014 USD ($) shares	Mar. 31, 2025 property shares	May 29, 2015 USD ($) shares	Mar. 14, 2024 USD ($) shares	Dec. 31, 2024 shares	Jan. 26, 2010 $ / shares shares
Organizational Structure [Line Items]
Common stock, shares issued (in shares)		148,516,246			148,516,246
Private Placement
Organizational Structure [Line Items]
Issuance of common stock (in shares)	258,462
Issuance of common stock, value \| $	$ 2.4
Office
Organizational Structure [Line Items]
Number of real estate properties \| property		13
Mixed-use Office/Retail Property
Organizational Structure [Line Items]
Number of real estate properties \| property		1
Common Stock
Organizational Structure [Line Items]
Issuance of common stock (in shares)			169,006,162
Issuance of common stock, value \| $			$ 1,700.0
Shares of common stock sold under dividend reinvestment plan (in shares)				46,154,757
Shares of common stock sold under dividend reinvestment plan, value \| $				$ 471.3
Redemptions of common stock (in shares)				74,644,349
Redemptions of common stock, value \| $				$ 789.2
KBS Capital Advisors LLC
Organizational Structure [Line Items]
Common stock, shares issued (in shares)						20,000
Common stock, purchase price per share (in dollars per share) \| $ / shares						$ 10.00
KBS Capital Advisors LLC \| Common Stock
Organizational Structure [Line Items]
Shares held by affiliate (in shares)		20,857
Operating Partnership
Organizational Structure [Line Items]
Partnership interest in operating partnership		0.10%
Partnership interest in the operating partnership and is its sole limited partner		99.90%