Debt Instrument, Amount Redeemed

No definition available.

Name:	dhc_DebtInstrumentAmountRedeemed
Namespace Prefix:	dhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Extension Term

+ References

No definition available.

+ Details

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Namespace Prefix:	dhc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Increase In Initial Interest Rate During Extension Period

+ References

No definition available.

+ Details

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Namespace Prefix:	dhc_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Initial Interest Rate During Extension Period

+ References

No definition available.

+ Details

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Namespace Prefix:	dhc_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Interest Rate, Accreted Value, Increase Rate, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	dhc_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Percentage Of Equity Interest As Collateral Guarantee

+ References

No definition available.

+ Details

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Namespace Prefix:	dhc_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of real estate properties serving as a collateral for debt, as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	dhc_NumberOfRealEstatePropertiesCollateralized
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

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Balance Type:	debit
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- 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.

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

- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of right-of-use asset from finance lease.

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Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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

- Definition

The effective interest rate during the reporting period.

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Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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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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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

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Indebtedness (Details)	1 Months Ended		3 Months Ended		9 Months Ended
Indebtedness (Details)	Feb. 28, 2023 USD ($)	Jan. 31, 2023 USD ($)	Sep. 30, 2024 USD ($) property	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) property	Sep. 30, 2023 USD ($)	Jun. 30, 2024 USD ($)	May 31, 2024 USD ($) property	Dec. 31, 2023 USD ($)	Dec. 21, 2023 USD ($)
Indebtedness
Number of properties owned (property) \| property			368		368
Aggregate net book value			$ 4,561,995,000		$ 4,561,995,000				$ 4,797,624,000
Repayments of lines of credit					0	$ 250,000,000
Loss on modification or early extinguishment of debt			$ 0	$ 0	$ 209,000	$ 1,075,000
Held for sale
Indebtedness
Number of properties owned (property) \| property			25		25
Finance Leased Properties
Indebtedness
Number of properties owned (property) \| property			2		2
Finance lease obligations			$ 2,743,000		$ 2,743,000
Finance leased asset, net			21,815,000		21,815,000
Mortgages
Indebtedness
Debt face amount								$ 120,000,000
Aggregate principal amount of mortgage debt			$ 127,889,000		$ 127,889,000
Number of properties owned (property) \| property			9		9
Aggregate net book value			$ 205,750,000		$ 205,750,000
Fixed annual interest rate								6.864%
Mortgages \| Medical Office And Life Science
Indebtedness
Number of properties owned (property) \| property								8
Senior Unsecured Notes, 9.75% due 2025
Indebtedness
Loss on modification or early extinguishment of debt					$ 209,000
Senior Secured Note due 2026 \| Held for sale
Indebtedness
Number of properties owned (property) \| property			22		22
Sales price					$ 302,100,000
Unsecured Debt
Indebtedness
Debt face amount			$ 2,040,000,000		2,040,000,000
Unsecured Debt \| Unsecured Revolving Credit Facility
Indebtedness
Unsecured revolving credit facility, maximum borrowing capacity	$ 450,000,000	$ 586,373,000								$ 450,000,000
Weighted average annual interest rate				8.30%		7.80%
Repayments of lines of credit	$ 136,373,000	$ 113,627,000
Loss on modification or early extinguishment of debt						$ 1,075,000
Secured Debts
Indebtedness
Debt face amount			940,534,000		940,534,000
Outstanding principal amount			1,070,598,000		1,070,598,000
Secured Debts \| Senior Secured Note due 2026
Indebtedness
Debt face amount			$ 940,534,000		$ 940,534,000
Number of real estate properties collateralized \| property			95		95
Equity interest in each collateral guarantee					100.00%
Accreted value increase rate			11.25%		11.25%
Amortization of debt discount			$ 22,034,000		$ 64,133,000
Debt extension term					1 year
Initial extension period interest rate			11.25%		11.25%
Increase in interest rate			0.50%		0.50%
Senior Notes \| Senior Unsecured Notes, 9.75% due 2025
Indebtedness
Debt face amount			$ 440,000,000		$ 440,000,000
Fixed annual interest rate			9.75%		9.75%		9.75%
Debt instrument redeemed							$ 60,000,000
Senior Notes \| Senior Unsecured Notes due 2031
Indebtedness
Debt face amount			$ 500,000,000		$ 500,000,000
Fixed annual interest rate			4.375%		4.375%
Unsecured Debt, Not Guaranteed
Indebtedness
Debt face amount			$ 1,100,000,000		$ 1,100,000,000
Senior Unsecured Notes \| Senior Unsecured Notes, 9.75% due 2025
Indebtedness
Outstanding principal amount			$ 440,000,000		$ 440,000,000
Fixed annual interest rate			9.75%		9.75%
Senior Unsecured Notes \| Senior Unsecured Notes due 2031
Indebtedness
Fixed annual interest rate			4.375%		4.375%