Commitments And Contingencies (Details)	9 Months Ended
Sep. 30, 2019 USD ($) properties	Dec. 31, 2018 USD ($)
Document Period End Date	Sep. 30, 2019
Unamortized lease incentive payments	$ 9,948,000	$ 7,456,000
Bickford Development Properties [Member]
Number Of Development Projects Active \| properties	5
Developer Incentive Payments	$ 250,000
Unamortized lease incentive payments	$ 1,750,000

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

No definition available.

+ Details

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

- Definition

This item represents contingent payments to developers which are an incentive to complete a construction project within the scheduled project time frame.

+ References

No definition available.

+ Details

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

- Definition

This item represents the number of active development or construction projects.

+ References

No definition available.

+ Details

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

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e40019-112707

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e40010-112707

+ Details

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

- Details

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