Schedule IV - Mortgage Loans on Real Estate Schedule IV - Mortgage Loans on Real Estate (Roll-Forward) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule IV - Mortgage Loans on Real Estate [Abstract]
Mortgage Loans on Real Estate, January 1	$ 34,926,000us-gaap_MortgageLoansOnRealEstate	$ 68,214,000us-gaap_MortgageLoansOnRealEstate	$ 78,672,000us-gaap_MortgageLoansOnRealEstate
Mortgage Loans on Real Estate, New Mortgage Loans	1,131,000	1,369,000	0
Mortgage Loans On Real Estate Total Additions	1,131,000	1,369,000	0
Settlement of mortgage note by real estate acquisition	0	13,741,000	0
Mortgage Loans On Real Estate, Impairment	0nhi_MortgageLoansOnRealEstateImpairment	4,037,000nhi_MortgageLoansOnRealEstateImpairment	2,300,000nhi_MortgageLoansOnRealEstateImpairment
Mortgage Loans on Real Estate, Collections of Principal	1,207,000	16,879,000	8,158,000
Mortgage Loans On Real Estate, Total Deductions	1,207,000	34,657,000	10,458,000
Mortgage Loans on Real Estate, December 31	$ 34,850,000us-gaap_MortgageLoansOnRealEstate	$ 34,926,000us-gaap_MortgageLoansOnRealEstate	$ 68,214,000us-gaap_MortgageLoansOnRealEstate

This element represents the total amount of other than temporary impairment charges taken during the current period.

No definition available.

Name:	nhi_MortgageLoansOnRealEstateImpairment
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the total amount of additions to mortgage loans during the reporting period.

+ References

No definition available.

+ Details

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

- Definition

The total amount of reductions in principal on mortgage loans.

+ References

No definition available.

+ Details

Name:	nhi_MortgageLoansOnRealEstateTotalDeductions
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	nhi_ScheduleIVMortgageLoansonRealEstateAbstract
Namespace Prefix:	nhi_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Settlement Of Mortgage Note By Real Estate Acquisition

+ References

No definition available.

+ Details

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

- Definition

Total carrying amount of mortgage loans as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 29

-Article 12

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29.6)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

+ Details

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

- Definition

The amount of principal collected on mortgage loans on real estate during the reporting period.

+ References

+ Details

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

- Definition

Total amount of new mortgage loans on real estate during the reporting period.

+ References

+ Details

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