Summary of Significant Accounting Policies - Debt Issuance Costs (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Amortization of deferred financing fees
Amortization expense in 2023	$ 7,169
Amortization expense in 2024	3,902
Amortization expense in 2025	2,754
Amortization expense in 2026	1,956
Amortization expense in 2027	1,956
Amortization expense thereafter	13,535
Unsecured Term Loans, Senior Notes, and Mortgage Notes Payable
Debt Instrument
Deb issuance costs, gross	47,661	$ 53,649
Accumulated amortization, debt issuance costs gross	19,791	15,800
Revolving Credit Facility
Debt Instrument
Deb issuance costs, gross	29,717	27,383
Accumulated amortization, debt issuance costs gross	$ 26,315	$ 22,899

No definition available.

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- Definition

Represents the amount of amortization of deferred financing fees expected to be recognized after the fifth succeeding fiscal year.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization of deferred financing fees expected to be recognized during year five of the five succeeding fiscal years.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization of deferred financing fees expected to be recognized during year four of the five succeeding fiscal years.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization of deferred financing fees expected to be recognized during year one of the five succeeding fiscal years.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization of deferred financing fees expected to be recognized during year three of the five succeeding fiscal years.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization of deferred financing fees expected to be recognized during year two of the five succeeding fiscal years.

+ References

No definition available.

+ Details

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Namespace Prefix:	dhc_
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- Definition

Amount of accumulated amortization of debt issuance costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

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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.

+ References

No definition available.

+ Details

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

+ Details

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