The initial rate charged under a lease entered into in connection with the purchase of a property.

No definition available.

Name:	nhi_InitialLeaseRate
Namespace Prefix:	nhi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents a lessee's payment to acquire a purchase option.

+ References

No definition available.

+ Details

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

- Definition

This concept reflects the interest rate to be received on a loan receivable.

+ References

No definition available.

+ Details

Name:	nhi_NoteReceivableInterestRate
Namespace Prefix:	nhi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the purchase commitment for real estate properties which the entity has entered into a binding agreement to acquire.

+ References

No definition available.

+ Details

Name:	nhi_RealEstatePropertiesCommitmentToPurchaseAmount
Namespace Prefix:	nhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the carrying value of a short-term real estate loan to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project, usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property. Note that there are separate concepts for the current and noncurrent portions of long-term construction loans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_ConstructionLoan
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LessorLeasingArrangementsOperatingLeasesTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at stated interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=75032840&loc=d3e61044-112788

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=75032840&loc=d3e61082-112788

+ Details

Name:	us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
Namespace Prefix:	us-gaap_
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

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfUnitsInRealEstateProperty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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

- Details

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

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

Subsequent Events Subsequent Events (Narrative) (Details)	1 Months Ended	12 Months Ended
	Jan. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) properties	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Jan. 12, 2018 USD ($) properties beds_or_units	Jan. 11, 2018 USD ($)
Subsequent Event [Line Items]
Payments to Acquire Real Estate		$ 157,214,000	$ 359,257,000	$ 106,315,000
Number of Real Estate Properties \| properties		209
Lessee Payment To Acquire Purchase Option		$ 1,250,000	$ 0	$ 0
Loans and Leases Receivable, Commitments, Fixed Rates		$ 103,000,000
Bickford Note Investment [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Initial lease rate						9.55%
Note Receivable Interest Rate						9.00%
Construction Loan						$ 1,490,000
Loans and Leases Receivable, Commitments, Fixed Rates	$ 14,000,000
Ensign Waxahachie Purchase [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Number of Units in Real Estate Property \| beds_or_units					121
Payments to Acquire Real Estate	$ 14,400,000
Lessor, Operating Lease, Term of Contract	13 years
Initial lease rate					8.20%
Number of Real Estate Properties \| properties					2
Real Estate Properties, Commitment To Purchase, Amount					$ 28,000,000
Lessee Payment To Acquire Purchase Option	$ 1,275,000