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

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=77888421&loc=SL77919311-209978

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=84173487&loc=SL77927221-108306

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919372-209981

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

Name:	us-gaap_StraightLineRent
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

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

- Details

Name:	us-gaap_MajorCustomersAxis=nhi_BickfordSeniorLivingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LeaseArrangementTypeAxis=nhi_SeptOct2019Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LeaseArrangementTypeAxis=nhi_June2023Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LeaseArrangementTypeAxis=nhi_May2031Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Real Estate Real Estate (Schedule of Bickford Leases) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($) properties	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) properties	Sep. 30, 2016 USD ($)
Number of Properties \| properties	207		207
Straight Line Rent Adjustment			$ 18,956	$ 16,583
Bickford Senior Living [Member]
Number of Properties \| properties	43		43
2017 Contractual Rent			$ 36,494
Straight Line Rent Adjustment			4,764
Straight Line Rent Adjustment	$ 1,600	$ 484	3,416	$ 482
Total Revenues			$ 41,258
Bickford Senior Living [Member] \| Sept / Oct 2019 [Member]
Number of Properties \| properties	10		10
2017 Contractual Rent			$ 8,994
Straight Line Rent Adjustment			(347)
Total Revenues			$ 8,647
Bickford Senior Living [Member] \| June 2023 [Member]
Number of Properties \| properties	13		13
2017 Contractual Rent			$ 10,809
Straight Line Rent Adjustment			226
Total Revenues			$ 11,035
Bickford Senior Living [Member] \| May 2031 [Member]
Number of Properties \| properties	20		20
2017 Contractual Rent			$ 16,691
Straight Line Rent Adjustment			4,885
Total Revenues			$ 21,576