Incentive Stock Option Granted Term Period

No definition available.

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Namespace Prefix:	nhi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Share Based Compensation Arrangements, Share Based Payment Award, Nonemployee Director, Annual Grant

+ References

No definition available.

+ Details

Name:	nhi_Nonemployeedirectorannualstockgrants
Namespace Prefix:	nhi_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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

- Details

Name:	us-gaap_AwardTypeAxis=nhi_TwoThousandTwelveStockOptionPlanMember
Namespace Prefix:
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- Details

Name:	us-gaap_AwardTypeAxis=nhi_PriorToShareholderApprovalofIncreaseMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=nhi_TwoThousandFiveStockOptionPlanMember
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- Details

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- Details

Name:	us-gaap_AwardTypeAxis=nhi_ExpectedToBeRecognizedDuring2016Member
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- Details

Name:	us-gaap_AwardTypeAxis=nhi_ExpectedToBeRecognizedDuring2017Member
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Share-Based Compensation (Narrative) (Details) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($) shares	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) $ / shares shares	Sep. 30, 2016 USD ($) $ / shares	May 07, 2015 shares	May 31, 2012 shares	May 31, 2005 shares
Nonemployee director annual stock grants \| shares			20,000
Stock or Unit Option Plan Expense	$ 405	$ 251	$ 2,270	$ 1,481
Unrecognized compensation cost	$ 959		$ 959
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares			$ 5.88	$ 3.65
2012 Plan [Member]
Shares available for grants \| shares	951,668		951,668		3,000,000	1,500,000
Stock Option Plan, Award Vesting Period			5 years
Common stock on date granted term period, years			10
Prior To Shareholder Approval of Increase [Member]
Nonemployee director annual stock grants \| shares			15,000
2005 Plan [Member]
Shares available for grants \| shares							1,500,000
Stock Option Plan, Award Vesting Period			10 years
Common stock on date granted term period, years			10
Expected To Be Recognized During 2015 [Member]
Unrecognized compensation cost	$ 342		$ 342
Expected To Be Recognized During 2016 [Member]
Unrecognized compensation cost	552		552
Expected To Be Recognized During 2017 [Member]
Unrecognized compensation cost	$ 65		$ 65