Schedule IV - Mortgage Loans on Real Estate (Summary Schedule) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Mortgage Loans on Real Estate [Abstract]
Mortgage Loans on Real Estate, Beginning Balance	$ 75,465	$ 94,588	$ 108,640
Mortgage Loans on Real Estate, New Mortgage Loans	6,566	12,422	4,501
Mortgage Loans on Real Estate, Other Additions	1,082	298
Total Additions	7,648	12,720	4,501
Settlement of mortgage not by real estate acquisition		22,936
Mortgage Loans on Real Estate, Collections of Principal	4,441	8,907	18,553
Total Deductions	4,441	31,843	18,553
Mortgage Loans on Real Estate, Ending Balance	$ 78,672	$ 75,465	$ 94,588

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

No definition available.

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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

- Definition

The settlement amount collected of mortgage loans by real estate acquisition during the reporting period.

+ References

No definition available.

+ Details

Name:	nhi_SettlementOfMortgageNotByRealEstateAcquisition
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29.6)

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

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 29

-Article 12

Reference 4: 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=6882300&loc=d3e5864-122674

+ Details

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

- Details

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

- 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

- Definition

Total amount of additions to mortgage loans other than new loans during the reporting period.

+ References

+ Details

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