EBP, Employer Matching Contributions, Net Of Forfeitures

No definition available.

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- Definition

EBP, Employer Prior-Year True-Up Contributions

+ References

No definition available.

+ Details

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- Definition

EBP, Merger Receivables

+ References

No definition available.

+ Details

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- Definition

EBP, Minimum Age To Participate In ESOP

+ References

No definition available.

+ Details

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- Definition

EBP, Noncash Company Ownership Contribution

+ References

No definition available.

+ Details

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

- Definition

EBP, Noncash Company Ownership True-Up Contributions

+ References

No definition available.

+ Details

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- Definition

EBP, Note Receivable From Participant, Account, Borrowing Term

+ References

No definition available.

+ Details

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- Definition

EBP, Note Receivable From Participant, Account, Primary Residence, Maximum Borrowing Term

+ References

No definition available.

+ Details

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- Definition

EBP, Participant Contribution, Automatic, Annual Increase Deferral Rate

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Specific Fund Selection, Transfer Restrictions, Maximum Invested Account Balance, Percentage

+ References

No definition available.

+ Details

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- Definition

EBP, Participant Loan, Basis Spread On Variable Rate

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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Period Type:	duration

- Definition

EBP, Plan Merger, Cash Receivables Transferred

+ References

No definition available.

+ Details

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Namespace Prefix:	hni_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

EBP, Plan Merger, Notes Receivable Transferred

+ References

No definition available.

+ Details

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Namespace Prefix:	hni_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of net asset available for benefit transferred to (from) employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from (to) external plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule III))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 45
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477063/962-205-45-8

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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

- Definition

Amount of allowance for credit loss on note receivable from participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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- Definition

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

+ References

+ Details

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- Details

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- Details

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- Details

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Description of the Plan - Narrative (Details) - EBP 001 - USD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Jan. 03, 2026
EBP, Description of Plan [Line Items]
Minimum age to participate in ESOP	18 years
Transfers related to merger		$ 13,668
Plan merger, cash receivables transferred	$ 5,307	349,860,565
Plan merger, notes receivable transferred	8,107	3,450,886
Plan merger, total receivables	$ 353,324,865
Maximum pretax and after-tax contributions	75.00%
Participant contribution, automatic, annual increase deferral rate	1.00%
Employer matching contributions, net of forfeitures	$ 25,576,016
Employer prior-year true-up contributions	8,348
Noncash company ownership contribution	4,994,445
Noncash company ownership true-up contributions	$ 2,562
Maximum percentage of invested account balance to allow transfer	25.00%
Note receivable from participant, account, maximum borrowing, amount			$ 50,000
Note receivable from participant, account, maximum borrowing, to total account, percentage			50.00%
Note receivable from participant, account, minimum borrowing, amount			$ 1,000
Primary residence, borrowing term	15 years
Note receivable from participant, account, basis spread on variable rate	1.00%
Allowance for credit losses	$ 0	$ 0
Minimum
EBP, Description of Plan [Line Items]
Participant contribution, automatic, deferral rate	3.00%
Maximum
EBP, Description of Plan [Line Items]
Participant contribution, automatic, deferral rate	10.00%
Note receivable from participant, account, borrowing term	60 months