XML 82 R60.htm IDEA: XBRL DOCUMENT
v3.20.4

Fair Value of Assets and Liabilities - Assets and Liabilities (Details) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Jan. 01, 2020 USD ($) shares | Dec. 31, 2020 USD ($) property shares | Dec. 31, 2019 USD ($) shares | Dec. 31, 2018 USD ($)
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Unrealized gains and losses on equity securities held |  | $ 34,106 | $ (462) |
Impairment of assets |  | 106,972 | 115,201 | $ 66,346
Five Star |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Distribution to common shareholders of the right to receive Five Star Senior Living Inc. common stock |  | $ 59,801 | 0 | 0
Five Star | Common Shares |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Issued (in shares) | shares | 10,268,158 |  |  |
Five Star |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Investment in common shares (in shares) | shares |  | 10,691,658 |  |
Unrealized gains and losses on equity securities held |  |  | $ 462 |
Five Star | Common Shares |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Investment in common shares (in shares) | shares |  | 10,691,658 | 423,500 |
Cost basis for shares owned |  | $ 44,448 |  |
Distribution to common shareholders of the right to receive Five Star Senior Living Inc. common stock | $ 38,095 |  |  |
Recurring | Five Star |  |  |  |
Recurring Fair Value Measurements Assets: |  |  |  |
Investments in Five Star |  | 73,772 | $ 1,571 |
Recurring | Five Star | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Recurring Fair Value Measurements Assets: |  |  |  |
Investments in Five Star |  | 73,772 |  |
Recurring | Five Star | Significant Other Observable Inputs (Level 2) |  |  |  |
Recurring Fair Value Measurements Assets: |  |  |  |
Investments in Five Star |  | 0 |  |
Recurring | Five Star | Significant Unobservable Inputs (Level 3) |  |  |  |
Recurring Fair Value Measurements Assets: |  |  |  |
Investments in Five Star |  | 0 |  |
Nonrecurring |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Real estate properties held for sale |  | 47,848 |  |
Nonrecurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Real estate properties held for sale |  | 0 |  |
Nonrecurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Real estate properties held for sale |  | 47,848 |  |
Nonrecurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Real estate properties held for sale |  | 0 |  |
Medical Office |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Impairment of assets |  | 8,558 | 43,035 | $ 46,797
Medical Office | Nonrecurring |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Sale price less estimated cost to sell |  | 9,000 |  |
Medical Office | Disposal Group, Held-for-sale, Not Discontinued Operations | Nonrecurring |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Impairment of assets |  | $ 3,378 |  |
Number of real estate properties held for sale | property |  | 1 |  |
Sale price less estimated cost to sell |  | $ 275 |  |
Senior Living Communities |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Impairment of assets |  | 98,414 | $ 72,166 |
Senior Living Communities | Nonrecurring |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Sale price less estimated cost to sell |  | 39,600 |  |
Senior Living Communities | Disposal Group, Held-for-sale, Not Discontinued Operations | Nonrecurring |  |  |  |
Non-Recurring Fair Value Measurements Assets: |  |  |  |
Impairment of assets |  | $ 25,797 |  |
Number of real estate properties held for sale | property |  | 10 |  |
Sale price less estimated cost to sell |  | $ 477 |  |

X
- Definition Assets Held-For-Sale, Purchase And Sale Agreement Less Estimated Costs To Sell + References No definition available. + Details
Name: | dhc_AssetsHeldForSalePurchaseAndSaleAgreementLessEstimatedCostsToSell
Namespace Prefix: | dhc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Historical Cost Basis For Shares Owned + References No definition available. + Details
Name: | dhc_HistoricalCostBasisForSharesOwned
Namespace Prefix: | dhc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The number of real estate properties owned by the entity, which are classified as held for sale as of the balance sheet date. + References No definition available. + Details
Name: | dhc_NumberOfRealEstatePropertiesHeldForSale
Namespace Prefix: | dhc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + Details
Name: | us-gaap_AssetImpairmentCharges
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fair value portion of assets classified as held for sale. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117546-209714 + Details
Name: | us-gaap_EquitySecuritiesFvNiUnrealizedGainLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_FairValueInputsQuantitativeInformationAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_FairValueMeasurementsNonrecurringValueMeasurementAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Balance held at close of period in number of shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section 50 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column B)) -URI http://asc.fasb.org/extlink&oid=120401592&loc=d3e611197-123010 + Details
Name: | us-gaap_InvestmentOwnedBalanceShares
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value portion of investments in an entity not consolidated. Includes, but is not limited to, investments in an entity that is affiliated with the reporting entity by means of direct or indirect ownership, an entity in which the reporting entity shares control of the entity with another party or group, an entity which the company has significant influence, but does not have control and subsidiaries that are not required to be consolidated and are accounted for using the equity or cost method. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVenturesFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of new stock issued during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_StockIssuedDuringPeriodValueNewIssues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=dhc_FiveStarQualityCareIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=dhc_FiveStarQualityCareIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=dhc_MedicalOfficeBuildingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=dhc_SeniorLivingCommunityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |