Real Estate (Schedule of Bickford Leases) (Details)	3 Months Ended
Mar. 31, 2020 USD ($) properties	Mar. 31, 2019 USD ($)
Number of Properties \| properties	225
Amortization of lease incentives	$ 236,000	$ 168,000
Bickford Senior Living [Member]
Number of Properties \| properties	48
2019 Contractual Rent	$ 50,420,000
2019 Straight Line Rent	3,769,000
Amortization of lease incentives	775,000
Total Revenues	$ 53,414,000
Bickford Senior Living [Member] \| June 2023 [Member]
Number of Properties \| properties	13
2019 Contractual Rent	$ 11,812,000
2019 Straight Line Rent	14,000
Amortization of lease incentives	0
Total Revenues	$ 11,826,000
Bickford Senior Living [Member] \| September 2024 [Member]
Number of Properties \| properties	10
2019 Contractual Rent	$ 9,343,000
2019 Straight Line Rent	339,000
Amortization of lease incentives	0
Total Revenues	$ 9,682,000
Bickford Senior Living [Member] \| May 2031 [Member]
Number of Properties \| properties	20
2019 Contractual Rent	$ 24,193,000
2019 Straight Line Rent	2,671,000
Amortization of lease incentives	775,000
Total Revenues	$ 26,089,000
Bickford Senior Living [Member] \| April 2033 [Member]
Number of Properties \| properties	5
2019 Contractual Rent	$ 5,072,000
2019 Straight Line Rent	745,000
Amortization of lease incentives	0
Total Revenues	$ 5,817,000

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

- Definition

Amount of amortization of lease incentive costs incurred by the lessor for the benefit of the lessee.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 6
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-Section 25
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-URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e40019-112707

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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=119202524&loc=SL77919372-209981

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=118952077&loc=SL77927221-108306

+ Details

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

- Definition

Amount of the adjustment to rental revenues to measure escalating leasing revenues on a straight line basis.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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