v3.25.2

Loans - Narrative, Past Due and Non-Accrual Loans (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2025	Dec. 31, 2024
Receivables [Abstract]
Non-accrual loans	$ 12,857	$ 14,264
Criteria days for delinquent status	90 days	90 days
Principal balance of loans on non accrual status, less than	$ 500
Impairment of loans	8,800	$ 9,600
Loans on non accrual status with principal balances below threshold definition of an impaired loan	4,100	4,700
90 days or more past due and accruing	1,200	1,200
Loans held-for-sale	$ 0	$ 4,897

Delinquent status classification criteria days minimum.

+ References

No definition available.

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- Definition

Loans deemed to be impaired non accrual amount.

+ References

No definition available.

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- Definition

Loans On Non Accrual Status With Principal Balances Below Threshold Definition Of An Impaired Loan

+ References

No definition available.

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- Definition

Principal balance threshold for non accrual status.

+ References

No definition available.

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- Definition

Amortized cost excluding accrued interest, of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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Balance Type:	debit
Period Type:	instant

- Definition

Amount, before valuation allowance, of financing receivable classified as held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477011/948-310-45-1

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Balance Type:	debit
Period Type:	instant

- References

No definition available.

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Northfield Bancorp, Inc. 10-Q