Common stock, purchase price per share.

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- Definition

Organizational Structure [Line Items]

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- Definition

Shares held by affiliate

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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

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- Definition

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

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- Definition

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

+ References

No definition available.

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- Definition

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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- Definition

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 Thousands			3 Months Ended		9 Months Ended		67 Months Ended	126 Months Ended
ORGANIZATION (Details) $ / shares in Units, $ in Thousands	Jul. 12, 2021 USD ($) shares	Oct. 03, 2014 USD ($) shares	Sep. 30, 2021 USD ($) property shares	Sep. 30, 2020 USD ($) shares	Sep. 30, 2021 USD ($) property shares	Sep. 30, 2020 USD ($) shares	May 29, 2016 USD ($) shares	Sep. 30, 2021 USD ($) property shares	Nov. 02, 2021 property	Dec. 31, 2020 shares	Jan. 26, 2010 $ / shares shares
Organizational Structure [Line Items]
Common stock, shares issued (in shares)			157,205,102		157,205,102			157,205,102		184,249,076
Issuance of common stock \| $			$ 6,507	$ 11,655	$ 32,792	$ 35,277
Redemptions of common stock (in shares)	26,377,990
Redemptions of common stock \| $	$ 272,700		$ 307,717	$ 2,343	$ 313,800	$ 8,635
Customer Concentration Risk \| Revenue \| Retail Tenants
Organizational Structure [Line Items]
Concentration risk, percentage			4.00%
Private Placement
Organizational Structure [Line Items]
Issuance of common stock (in shares)		258,462
Issuance of common stock \| $		$ 2,400
Office Properties
Organizational Structure [Line Items]
Number of real estate properties \| property			17		17			17
Office Properties \| Held-for-sale
Organizational Structure [Line Items]
Number of real estate properties \| property			1		1			1
Office Properties \| Disposed of by Sale \| Subsequent Event
Organizational Structure [Line Items]
Number of real estate properties \| property									1
Mixed-use Office/Retail Property
Organizational Structure [Line Items]
Number of real estate properties \| property			1		1			1
Common Stock
Organizational Structure [Line Items]
Issuance of common stock (in shares)			636,041	1,052,825	3,209,068	3,186,782	169,006,162
Issuance of common stock \| $			$ 6	$ 11	$ 32	$ 32	$ 1,700,000
Shares of common stock sold under dividend reinvestment plan, shares								39,883,754
Shares of common stock sold under dividend reinvestment plan, value \| $								$ 412,100
Redemptions of common stock (in shares)			29,686,941	201,155	30,253,042	741,247		59,684,490
Redemptions of common stock \| $			$ 296	$ 3	$ 302	$ 8		$ 636,100
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		20,857			20,857
KBS Limited Partnership III
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%