SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	9 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	Sep. 30, 2025
Accounting Policies [Abstract]
Principles of Consolidation and Basis of Presentation	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, 2025 are not necessarily indicative of the results that may be expected for the year ending December 31, 2025. The consolidated financial statements include the accounts of the Company, REIT Holdings III, the Operating Partnership and their direct and indirect wholly owned subsidiaries. All significant intercompany balances and transactions are eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of the consolidated financial statements and condensed notes thereto in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and condensed notes. Actual results could materially differ from those estimates.
Reclassifications	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 prior periods.
Comprehensive Income (Loss)	Comprehensive Income (Loss) Comprehensive income (loss) for the three and nine months ended September 30, 2025 and 2024 was equal to net income (loss) for these respective periods.
Derivative Instruments	Derivative Instruments Cash Flow Classification of Derivative Settlements The Company classifies proceeds received or amounts paid related to early terminations or settlements of its derivative instruments not designated as hedges for accounting purposes in cash flows from operating activities in the statement of cash flows. During the nine months ended September 30, 2024, the Company terminated two interest rate swap agreements and received aggregate settlement proceeds of $6.6 million which was included in net cash flow provided by operating activities in the accompanying consolidated statement of cash flows.
Per Share Data	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.
Recently Issued Accounting Standards Update	Recently Issued Accounting Standards Update In November 2024, the FASB issued accounting standards update (“ASU”) No. 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”). ASU 2024-03 requires public entities to disaggregate, in a tabular presentation, certain income statement expenses into different categories, such as purchases of inventory, employee compensation, depreciation, and intangible asset amortization. The guidance is effective for fiscal years beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted and should be applied either (1) prospectively to financial statements issued for reporting periods after the effective date or (2) retrospectively to any or all prior periods presented in the financial statements. The Company is currently evaluating the impact of the adoption of ASU 2024-03 on its consolidated financial statements and future disclosures but does not expect the adoption of ASU 2024-03 to have a material impact on its consolidated financial statements.
Fair Value Measurement	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.

Disclosure of accounting policy for its derivative instruments and hedging activities.

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+ Details

- Definition

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

+ References

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+ Details

KBS Real Estate Investment Trust III, Inc. 10-Q