Basis of Presentation	9 Months Ended
Basis of Presentation	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements of Diversified Healthcare Trust and its subsidiaries, or we, us, or our, are unaudited. Certain information and disclosures required by U.S. generally accepted accounting principles, or GAAP, for complete financial statements have been condensed or omitted. We believe the disclosures made are adequate to make the information presented not misleading. However, the accompanying condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes contained in our Annual Report on Form 10-K for the year ended December 31, 2022, or our Annual Report. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair statement of results for the interim period have been included. All intercompany transactions and balances with or among our consolidated subsidiaries have been eliminated. Operating results for interim periods are not necessarily indicative of the results that may be expected for the full year. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect reported amounts. Actual results could differ from those estimates. Significant estimates in our condensed consolidated financial statements include purchase price allocations, useful lives of fixed assets and impairments of real estate and intangible assets. We have been, are currently, and expect in the future to be involved in claims, lawsuits, and regulatory and other governmental audits, investigations and proceedings arising in the ordinary course of our business, some of which may involve material amounts. Also, the defense and resolution of these claims, lawsuits, and regulatory and other governmental audits, investigations and proceedings may require us to incur significant expense. We account for claims and litigation losses in accordance with the Financial Accounting Standards Board Accounting Standards Codification Topic 450, Contingencies, or ASC 450. Under ASC 450, loss contingency provisions are recorded for probable and estimable losses at our best estimate of a loss or, when a best estimate cannot be made, at our estimate of the minimum loss. These estimates are often developed prior to knowing the amount of the ultimate loss, require the application of considerable judgment, and are refined as additional information becomes known. Accordingly, we are often initially unable to develop a best estimate of loss and therefore the estimated minimum loss amount, which could be zero, is recorded; and then, as information becomes known, the minimum loss amount is updated, as appropriate. A minimum or best estimate amount may be increased or decreased when events result in a changed expectation. Going Concern The senior living industry has been adversely affected by a slow recovery from the COVID-19 pandemic, as well as economic and market conditions. These conditions continue to have a significant negative impact on our results of operations, financial position and cash flows. Although there have been signs of recovery and increased demand when compared to the low levels during the COVID-19 pandemic, the recovery of our senior housing operating portfolio, or SHOP, segment has been slower than previously anticipated and uneven, and we cannot be sure when or if the senior living business will return to historic pre-pandemic levels. To mitigate the effects of the slow recovery coming from the COVID-19 pandemic and the increased variability in operating cash flows from our SHOP communities, we continue to work with our senior living operators to manage costs, especially labor costs, and to increase rates and occupancy. However, increased operating costs resulting from difficult labor market conditions, wage and commodity price inflation and increased insurance costs, among other things, continue to negatively impact margins. Additionally, while our senior living operators have increased rates, those rates are increasing gradually and are not increasing at the same pace as our costs, putting further pressure on our margins. In order to increase the probability of a recovery of our cash flows, we have continued to invest capital in our SHOP segment, which has reduced our cash balances since the filing of our Annual Report on March 1, 2023. As a result of our decreased cash balances, we have deferred, and may continue to defer, future capital expenditures to preserve liquidity, which may slow the pace of any recovery of our cash flows. As of September 30, 2023, our ratio of consolidated income available for debt service to debt service was below the 1.5x incurrence requirement under our credit agreement and our public debt covenants, and we cannot be certain how long this ratio will remain below 1.5x. We are unable to refinance existing or maturing debt or issue new debt until this ratio is at or above 1.5x on a pro forma basis. As of September 30, 2023, we had $278,122 of cash and cash equivalents and $700,000 of outstanding debt due within one year from the date of issuance of these financial statements, including $450,000 in outstanding borrowings under our credit facility, which matures on January 15, 2024, and $250,000 of senior notes that mature on May 1, 2024. Our credit facility is secured by 62 properties which had an appraised value of approximately $1,114,270 based on appraisals completed in 2023. Based on the challenges described above, as well as our reduced cash balances, additional capital commitments in both our Office Portfolio and SHOP segments and upcoming debt maturities, we have concluded that there is substantial doubt about our ability to continue as a going concern for at least one year from the date of issuance of these financial statements. In September 2023, subsequent to the termination of our proposed merger with Office Properties Income Trust, or OPI, we engaged B. Riley Securities, Inc., or B. Riley, as a financial advisor to help us evaluate our options to address our near term capital needs, including the upcoming debt maturities described above. Among the alternatives being considered to address our near term capital needs are raising permissible new capital, including by selling assets, as well as seeking an extension of the maturity date of our credit facility. Regarding any new capital that may be raised, we are limited in the type of financings we can pursue as we cannot currently refinance existing or maturing debt or issue new debt, as described above. We are also engaging in discussions with the lenders under our $450,000 credit facility regarding an amendment to our credit agreement to extend the maturity date of the facility, amend certain covenants and allow us to repay maturing debt, among other things. While we believe that the new capital we expect to raise, including proceeds from our planned asset sales, and the possible extension of the maturity date of our credit facility, will alleviate the substantial doubt about our ability to continue as a going concern, we cannot provide assurance that we will raise new capital or sell assets or that any new capital raised, including proceeds from our planned asset sales, will be sufficient to repay our maturing debt or that our lenders will agree to an extension of the maturity date of our credit facility. Due to challenging capital market conditions, in particular with respect to commercial real estate, we do not believe that it is probable, as of the date of issuance of these financial statements, that we will raise sufficient new capital, including proceeds from our planned asset sales, to meet our upcoming contractual commitments. As of November 1, 2023, we cannot demonstrate that our management's plans to alleviate the substantial doubt about our ability to continue as a going concern will be probable in mitigating the conditions that raise the substantial doubt because our plan to raise permissible new capital, including proceeds from our planned asset sales, and to extend the maturity date of our credit facility, is subject to market conditions and lender approvals, among other things, which are beyond our control. Our condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty. Termination of Merger Agreement with Office Properties Income Trust On April 11, 2023, we and OPI entered into an Agreement and Plan of Merger, or the Merger Agreement, pursuant to which we and OPI agreed that we would merge with and into OPI, with OPI as the surviving entity in the merger, subject to the terms and conditions of the Merger Agreement. On September 1, 2023, we and OPI mutually agreed to terminate the Merger Agreement and entered into a termination agreement, or the Termination Agreement. The mutual termination of the Merger Agreement was separately recommended by special committees of our and OPI’s respective board of trustees and approved by our and OPI’s respective board of trustees. Pursuant to the Termination Agreement, the termination of the Merger Agreement was effective as of September 1, 2023. Neither we nor OPI are required to pay any termination fee as a result of the mutual decision to terminate the Merger Agreement. We and OPI will bear our and its respective costs and expenses related to the Merger Agreement and the transactions contemplated thereby in accordance with the terms of the Merger Agreement.