Name:	dei_DocumentPeriodEndDate
Namespace Prefix:	dei_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

Asset Purchase Transaction Costs

No definition available.

Name:	nhi_AssetPurchaseTransactionCosts
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

This element represents the total amount of capital improvements that an entity has committed to complete.

No definition available.

Name:	nhi_CapitalImprovementsCommitment
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

This item represents contingent payments that would be due to a development manager if certain operating metrics or performance thresholds were met.

No definition available.

Name:	nhi_ContingentIncentivePayments
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The initial rate charged under a lease entered into in connection with the purchase of a property.

No definition available.

Name:	nhi_InitialLeaseRate
Namespace Prefix:	nhi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

This item represents consideration received in exchange for granting an amendment to a lease agreement.

No definition available.

Name:	nhi_LeaseAmendmentConsideration
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

This item represents the maximum amount a lease will escalate each year.

No definition available.

Name:	nhi_LeaseEscalatorMaximum
Namespace Prefix:	nhi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

This item represents the minimum rate a lease payment escalates each year.

No definition available.

Name:	nhi_LeaseEscalatorMinimum
Namespace Prefix:	nhi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The initial lease escalator to be charged starting after lease year 4 under a lease entered into in connection with the purchase of a property.

No definition available.

Name:	nhi_LeaseEscalatorRateafterLeaseYear4
Namespace Prefix:	nhi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

This item relates to the percent of facility NOI to be paid as lease payment.

No definition available.

Name:	nhi_LeasePaymentNOIBasedPercent
Namespace Prefix:	nhi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

This item represents the number of shares of a lessor that are owned by a significant lessee as of the end of the reporting period.

No definition available.

Name:	nhi_LessorEquitySharesOwnedSignificantLessee
Namespace Prefix:	nhi_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

This item represents the amount of loan and realty impairments net of any applicable gains or recoveries.

No definition available.

Name:	nhi_LoanandLeaseLossesandRecoveriesNet
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

This element represents the minimum annual lease income to be received.

No definition available.

Name:	nhi_MinimumAnnualLeaseIncome
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

This item represents the original cost of corporate assets that are not part of the investment portfolio.

No definition available.

Name:	nhi_NonportfolioAssetsOriginalCost
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Number Of Additional Lease Renewal Options

No definition available.

Name:	nhi_NumberOfAdditionalLeaseRenewalOptions
Namespace Prefix:	nhi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

The number of lessees of real estate property at the end of the period.

No definition available.

Name:	nhi_NumberOfLessees
Namespace Prefix:	nhi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Number Of Real Estate Properties Acquired

No definition available.

Name:	nhi_NumberOfRealEstatePropertiesAcquired
Namespace Prefix:	nhi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

This item relates to the number of lease portfolios which is group of properties leased through one or more leases to the same operator or to related operators.

No definition available.

Name:	nhi_NumberofLeasePortfolios
Namespace Prefix:	nhi_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

Number of Master Leases

No definition available.

Name:	nhi_NumberofMasterLeases
Namespace Prefix:	nhi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

This item relates to payments made as part of an asset acquisition that have been reserved for working capital needs related to the acquired asset.

No definition available.

Name:	nhi_PaymentsRelatedToAssetAcquisitionReservedForWorkingCapital
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

This element represents the percentage of income recognized from a lease tenant.

No definition available.

Name:	nhi_PercentageOfContinuingRevenue
Namespace Prefix:	nhi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

This element represents the rental revenue rate earned during the period from lessee-operators based on revenues generated in their operations, generally in excess of a base amount. Generally stipulated in the lease agreement, it usually will provide for a fixed percentage of revenue to be paid as additional (or possibly only) rent due the lessor, and may be based on gross revenues, net revenues, or multiple variations thereof.

No definition available.

Name:	nhi_PercentageRentRate
Namespace Prefix:	nhi_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

This item represents the amount of an outstanding purchase option.

No definition available.

Name:	nhi_PurchaseOptionAmount
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The element represents the original cost of all portfolio leased assets.

No definition available.

Name:	nhi_RealEstateInvestmentPropertyPortfolioAssets
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Real Estate Investments During The Period

No definition available.

Name:	nhi_RealEstateInvestmentsDuringThePeriod
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

This item represents an accumulated straight-line rent receivable balance written off as a result of a lease amendment or termination.

No definition available.

Name:	nhi_WriteOffOfStraightLineRentReceivable
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Name:	us-gaap_EscrowDeposit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

This item represents the deferred charge for an incentive or inducement granted by a lessor to a lessee, in order to motivate the lessee to enter the lease agreement, which incentive or inducement is to be recognized as a reduction of rental revenue over the lease term.

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Name:	us-gaap_IncentiveToLessee
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Term of lessor's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Name:	us-gaap_LessorOperatingLeaseRenewalTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Name:	us-gaap_LessorOperatingLeaseTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

The minimum amount the entity agreed to spend under the long-term purchase commitment.

No definition available.

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

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

No definition available.

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

No definition available.

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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

No definition available.

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

The number of states the entity operates in as of the balance sheet date.

No definition available.

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

The number of units in a real estate property owned as of the balance sheet date.

No definition available.

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

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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-Name Accounting Standards Codification
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-Section 25
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-URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e39896-112707

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

The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner.

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-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

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-Name Accounting Standards Codification
-Topic 944
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(f))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Name:	us-gaap_RealEstateHeldforsale
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Difference between actual rental income due and rental income recognized on a straight-line basis.

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-Name Accounting Standards Codification
-Topic 230
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-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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

Name:	srt_MajorCustomersAxis=nhi_WingateHealthcareMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MajorCustomersAxis=nhi_HolidayLeaseAmendmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MajorCustomersAxis=nhi_HolidayAcquisitionHoldingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MajorCustomersAxis=nhi_ComfortCareSeniorLivingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	invest_InvestmentAxis=nhi_April2019Member
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	invest_InvestmentAxis=nhi_May2019Member
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_MajorCustomersAxis=nhi_DiscoverySeniorLivingMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	invest_InvestmentAxis=nhi_JointVentureEquityInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	invest_InvestmentAxis=nhi_JointVentureNoncontrollingEquityInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	invest_InvestmentAxis=nhi_JointVenturePreferredEquityInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	invest_InvestmentAxis=nhi_JointVentureControllingEquityInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	invest_InvestmentAxis=us-gaap_LandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	invest_InvestmentAxis=us-gaap_BuildingAndBuildingImprovementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MajorCustomersAxis=nhi_BAKAEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_MajorCustomersAxis=nhi_BickfordSeniorLivingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MajorCustomersAxis=nhi_SeniorLivingCommunitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MajorCustomersAxis=nhi_NationalHealthcareCorporationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	invest_InvestmentAxis=nhi_NHC1991LeaseMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	invest_InvestmentAxis=nhi_NHC2013LeaseMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_MajorCustomersAxis=nhi_NonPerformingLeaseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MajorCustomersAxis=nhi_SHRegencyLeasingLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_MajorCustomersAxis=nhi_ChancellorHealthCareMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_MajorCustomersAxis=nhi_SHRegencyTransitionPropertiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=nhi_SeniorHousingCommunityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=nhi_SkilledNursingFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	invest_InvestmentAxis=nhi_SubleasedFacilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=nhi_HospitalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=nhi_MedicalOfficeBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=nhi_AssistedLivingFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=nhi_IndependentLivingFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=nhi_MemoryCareMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_InvestmentTypeAxis=nhi_ContingentPaymentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_InvestmentTypeAxis=nhi_AssistedLivingFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_InvestmentTypeAxis=nhi_VeroBeachAcquisitionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_InvestmentTypeAxis=nhi_RightofFirstOfferMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_InvestmentTypeAxis=nhi_HolidayLeaseAmendmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	invest_InvestmentAxis=nhi_ForfeitureAmountMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	invest_InvestmentAxis=nhi_CashPortionMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_InvestmentTypeAxis=nhi_PriortoLeaseAmendmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_InvestmentTypeAxis=nhi_AssetHeldForSaleMember
Namespace Prefix:
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