Commitments And Contingencies (Narrative) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) properties beds_or_units	Dec. 31, 2020 USD ($)
Maximum Commitment For All Active Development Projects	$ 28,395
Development in Process	23,445
Contingent Funding Commitment	$ 31,900
Number of Properties \| properties	228
Lease deposit liabilities	$ 10,638	$ 10,638
Lease Payment Deferral [Member]
Operating Lease, Lease Income	9,179
Lease Abatement [Member]
Operating Lease, Lease Income	$ 2,150
Initial Interest Rate [Member]
Deferred Lease Payments, Accrual Interest Rate	8.00%
Discovery PropCo [Member]
Maximum Commitment For All Active Development Projects	$ 2,000
Bickford Senior Living [Member]
Number of Properties \| properties	48
Bickford Senior Living [Member] \| Lease Payment Deferral [Member]
Operating Lease, Lease Income	$ 7,500
Bickford Senior Living [Member] \| Lease Abatement [Member]
Operating Lease, Lease Income	$ 2,100
Senior Living Communities [Member]
Number of Properties \| properties	10
Holiday Acquisition Holdings [Member]
Number of Properties \| properties	26
Lease deposit liabilities	$ 10,600
Other Than Bickford \| Lease Payment Deferral [Member]
Operating Lease, Lease Income	1,679
Other Than Bickford \| Lease Abatement [Member]
Operating Lease, Lease Income	50
Development Commitment [Member] \| Discovery PropCo [Member]
Development in Process	$ 1,000
Lease Inducement [Member]
Number of Properties \| beds_or_units	6
Contingent Funding Commitment, Amount Funded	$ 1,500
Lease Inducement [Member] \| Navion Senior Solutions [Member]
Contingent Funding Commitment, Amount Funded	$ 1,000
Rent Deferred Second Quarter of 2021 \| Lease Payment Deferral [Member]
Number of Operators/Tenants \| beds_or_units	4
Rent Deferred Second Quarter of 2021 \| Bickford Senior Living [Member] \| Lease Payment Deferral [Member]
Operating Lease, Lease Income	$ 5,000
Rent Deferred Second Quarter of 2021 \| Other Than Bickford \| Lease Payment Deferral [Member]
Operating Lease, Lease Income	2,300
Rent Deferred First Quarter of 2021 \| Lease Payment Deferral [Member]
Operating Lease, Lease Income	4,197
Rent Deferred First Quarter of 2021 \| Bickford Senior Living [Member] \| Lease Payment Deferral [Member]
Operating Lease, Lease Income	3,750
Rent Deferred First Quarter of 2021 \| Other Than Bickford \| Lease Payment Deferral [Member]
Operating Lease, Lease Income	$ 447

This item represents the maximum amount of a contingent funding commitment.

No definition available.

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

- Definition

This item represents the amount of a contingent funding commitment which has been funded.

+ References

No definition available.

+ Details

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

- Definition

This item represents the interest rate to be accrued on the outstanding balance from deferred lease payments.

+ References

No definition available.

+ Details

Name:	nhi_DeferredLeasePaymentsAccrualInterestRate
Namespace Prefix:	nhi_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the maximum commitment for all active development projects.

+ References

No definition available.

+ Details

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

- Definition

This item represents the number of operators or tenants.

+ References

No definition available.

+ Details

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

- Definition

The current amount of expenditures for a real estate project that has not yet been completed.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.10)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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

- 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

Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919372-209981

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123420820&loc=SL77919311-209978

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=124502072&loc=SL77927221-108306

+ Details

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

- Definition

This element represents money paid in advance to protect the provider of a product or service, such as a lessor, against damage or nonpayment by the buyer or tenant (lessee) during the term of the agreement. Such damages may include physical damage to the property, theft of property, and other contractual breaches. Security deposits held may be interest or noninterest bearing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15(a))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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

- Details

Name:	nhi_LeaseConcessionsAxis=nhi_LeasePaymentDeferralMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	nhi_LeaseConcessionsAxis=nhi_LeaseAbatementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	nhi_LeaseConcessionsAxis=nhi_InitialInterestRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

Name:	us-gaap_InvestmentTypeAxis=nhi_RentDeferredSecondQuarterOf2021Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=nhi_RentDeferredFirstQuarterOf2021Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: