Significant Accounting Policies Significant Accounting Policies (Details)	Sep. 30, 2019 properties
Lessor, Lease, Description [Line Items]
Lessor, Operating Lease, Renewal Term	5 years
Variable Interest Entity Number Of Entities Not Primary Beneficiary	7
Minimum [Member]
Lessor, Lease, Description [Line Items]
Lessor, Operating Lease, Term of Contract	10 years
Maximum [Member]
Lessor, Lease, Description [Line Items]
Lessor, Operating Lease, Term of Contract	15 years

Number of Variable Interest Entities (VIE) or potential VIEs for which it is determined that the reporting entity is not the primary beneficiary.

No definition available.

+ Details

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

- 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

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919359-209981

+ Details

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

- Definition

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

+ References

+ Details

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

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type: