The net difference between the derecognized operating lease right-of-use assets and operating lease liabilities.

No definition available.

Name:	nhc_LesseeOperatingLeaseNetDifferenceBetweenDerecognitionOfPreexistingBalances
Namespace Prefix:	nhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease that has been dereocognized.

+ References

No definition available.

+ Details

Name:	nhc_LesseeOperatingLeaseOperatingLeaseLiabilityDerecognized
Namespace Prefix:	nhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of lessee's right to use underlying asset under operating lease that has been derecognized.

+ References

No definition available.

+ Details

Name:	nhc_LesseeOperatingLeaseRightofuseAssetDerecognized
Namespace Prefix:	nhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of independent living facilities acquired during the period.

+ References

No definition available.

+ Details

Name:	nhc_NumberOfIndependentLivingFacilitiesAcquired
Namespace Prefix:	nhc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of skilled nursing beds acquired during the period.

+ References

No definition available.

+ Details

Name:	nhc_NumberOfSkilledNursingBedsAcquired
Namespace Prefix:	nhc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of skilled nursing facilities acquired during the period.

+ References

No definition available.

+ Details

Name:	nhc_NumberOfSkilledNursingFacilitiesAcquired
Namespace Prefix:	nhc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of skilled nursing facilities that are subleased to third parties.

+ References

No definition available.

+ Details

Name:	nhc_NumberOfSubleasedSkilledNursingFacilities
Namespace Prefix:	nhc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of expense for acquisition-related cost incurred to effect business combination. Includes, but is not limited to, finder's fee; advisory, legal, accounting, valuation, and other professional and consulting fees; and general administrative cost, including cost of maintaining internal acquisition department.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-7

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 25
-Paragraph 23
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479405/805-10-25-23

+ Details

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

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479303/805-10-55-41

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-8

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479581/805-30-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479581/805-30-50-1

+ Details

Name:	us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of acquiree's revenue since acquisition date of business combination included in consolidated statement of income.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-8

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 49
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479303/805-10-55-49

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

+ Details

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

- Details

Name:	us-gaap_BusinessAcquisitionAxis=nhc_FiveSkilledNursingFacilitiesAcquiredInJune2026Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=nhc_July2026AcquisitionsFromNationalHealthInvestorsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 3 - Acquisitions (Details Textual)			3 Months Ended		5 Months Ended	9 Months Ended
Note 3 - Acquisitions (Details Textual)	Jul. 01, 2026 USD ($)	Jun. 01, 2026 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Jun. 01, 2026	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)
Number of Skilled Nursing Facilities Acquired					5
Five Skilled Nursing Facilities Acquired in June 2026 [Member]
Number of Skilled Nursing Facilities Acquired		5
Business Combination, Consideration Transferred		$ 50,500,000
Number of Skilled Nursing Beds Acquired		639
Business Combination, Acquiree's Revenue since Acquisition Date, Actual			$ 19,288,000	$ 2,658,000		$ 25,290,000	$ 3,268,000
July 2026 Acquisitions from National Health Investors [Member]
Number of Skilled Nursing Facilities Acquired	32
Business Combination, Consideration Transferred	$ 560,000,000
Number of Independent Living Facilities Acquired	3
Number of Subleased Skilled Nursing Facilities	4
Lessee, Operating Lease, Right-of-use Asset Derecognized	$ 16,197,000
Lessee, Operating Lease, Operating Lease Liability Derecognized	15,763,000
Lessee, Operating Lease, Net Difference Between Derecognition of Pre-existing Balances	434,000
Business Combination, Acquisition-Related Cost, Expense	$ 3,906,000