Number of Real Estate Properties Under Agreement

No definition available.

Name:	dhc_NumberOfRealEstatePropertiesUnderAgreement
Namespace Prefix:	dhc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

This element represents the aggregate sales price excluding closing costs, of real estate properties sold by the entity.

+ References

No definition available.

+ Details

Name:	dhc_RealEstateAggregateSalesPrice
Namespace Prefix:	dhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfRealEstateProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 976
-SubTopic 310
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477332/976-310-50-1

+ Details

Name:	us-gaap_RealEstateLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

+ Details

Name:	us-gaap_RepaymentsOfSeniorDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=dhc_SeniorSecuredNotesZeroCouponRateDue2026Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DisposalGroupClassificationAxis=us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=dhc_SubsequentPropertiesDisposedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DisposalGroupClassificationAxis=us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Real Estate and Other Investments - Acquisitions and Dispositions Narrative (Details) $ in Thousands		1 Months Ended		9 Months Ended
	Nov. 03, 2025 USD ($) property	Nov. 03, 2025 USD ($) property	Oct. 31, 2025 USD ($) property	Sep. 30, 2025 USD ($) property
Real Estate
Number of properties owned (property)				335
Senior Secured Note Due 2026 \| Subsequent Event
Real Estate
Redemption of senior notes \| $	$ 90,529
Disposed of by sale
Real Estate
Number of properties owned (property)				32
Sales price \| $				$ 353,675
Disposed of by sale \| Subsequent Event \| Subsequent Properties Disposed
Real Estate
Number of properties owned (property)	12	12
Sales price \| $		$ 42,130
Disposed of by sale \| Senior Secured Note Due 2026
Real Estate
Redemption of senior notes \| $				$ 299,158
Disposed of by sale \| Senior Secured Note Due 2026 \| Subsequent Event
Real Estate
Number of properties owned (property)			1
Redemption of senior notes \| $			$ 10,249
Held for sale
Real Estate
Number of properties owned (property)				50
Held for sale \| Subsequent Event
Real Estate
Number of properties owned (property)	38	38
Sales price \| $	$ 237,219
Held for sale \| Senior Secured Note Due 2026 \| Subsequent Event
Real Estate
Number of real estate properties under agreement	12	12