Note 18 - Subsequent Event (Details Textual)		6 Months Ended
Jul. 01, 2026 USD ($)	Jun. 30, 2026 USD ($)
Subsequent Event [Member] \| July 2026 Credit Agreement [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 550,000,000
Debt Instrument, Term (Year)	5 years
Subsequent Event [Member] \| July 2026 Credit Agreement [Member] \| Minimum [Member]
Debt Instrument, Interest Rate, Base Rate	1.00%
Line of Credit Facility, Commitment Fee Percentage	0.20%
Subsequent Event [Member] \| July 2026 Credit Agreement [Member] \| Maximum [Member]
Line of Credit Facility, Commitment Fee Percentage	0.30%
Subsequent Event [Member] \| July 2026 Credit Agreement [Member] \| Secured Overnight Financing Rate (SOFR) [Member]
Debt Instrument, Interest Rate, Base Rate	1.00%
Debt Instrument, Funding Day Interest Rate	1.50%
Subsequent Event [Member] \| July 2026 Credit Agreement [Member] \| Secured Overnight Financing Rate (SOFR) [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate	1.25%
Subsequent Event [Member] \| July 2026 Credit Agreement [Member] \| Secured Overnight Financing Rate (SOFR) [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate	1.75%
Subsequent Event [Member] \| July 2026 Credit Agreement [Member] \| Base Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	0.75%
Debt Instrument, Funding Day Interest Rate	0.50%
Subsequent Event [Member] \| July 2026 Credit Agreement [Member] \| Base Rate [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate	0.25%
Subsequent Event [Member] \| July 2026 Credit Agreement [Member] \| Federal Funds Rate [Member]
Debt Instrument, Interest Rate, Base Rate	0.50%
Subsequent Event [Member] \| July 2026 Credit Agreement [Member] \| Term Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 475,000,000
Proceeds from Issuance of Long-Term Debt	475,000,000
Subsequent Event [Member] \| July 2026 Credit Agreement [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	75,000,000
Proceeds from Issuance of Long-Term Debt	$ 55,000,000
July 2026 Acquisitions from National Health Investors [Member]
Payments for Deposits in Escrow Accounts		$ 20,000,000
July 2026 Acquisitions from National Health Investors [Member] \| Subsequent Event [Member]
Number of Skilled Nursing Facilities Acquired	32
Number of Independent Living Facilities Acquired	3
Business Combination, Consideration Transferred	$ 560,000,000
Number of Subleased Skilled Nursing Facilities	4

The interest rate at funding day for the debt instrument.

No definition available.

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Namespace Prefix:	nhc_
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Balance Type:	na
Period Type:	duration

- Definition

The interest rates used in determining the base rate.

+ References

No definition available.

+ Details

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Namespace Prefix:	nhc_
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Balance Type:	na
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- Definition

The number of independent living facilities acquired during the period.

+ References

No definition available.

+ Details

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

- Definition

The number of skilled nursing facilities acquired during the period.

+ References

No definition available.

+ Details

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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

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

- Definition

The cash outflow associated with the deposits in escrow accounts.

+ References

No definition available.

+ Details

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Namespace Prefix:	nhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period between issuance and maturity of debt instrument, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480657/210-10-S50-8

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(i)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479886/946-10-S99-3

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

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

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