v3.25.3

Other Comprehensive Income - Schedule of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Disclosure Of Other Comprehensive Income Loss [Abstract]
Net amortization of bond premiums	$ 113	$ 146	$ 404	$ 431
Tax effect	(31)	(39)	(109)	(116)
Net income (loss)	82	107	295	315
Net interest expense on swaps		(21)		(21)
Tax effect		6		6
Net income (loss)		(15)		(15)
Total reclassification adjustments	$ 82	$ 92	$ 295	$ 300

Disclosure of Other Comprehensive Income Loss

+ References

No definition available.

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- Definition

Other comprehensive income (loss) reclassification adjustment from AOCI for interest expense (income) on swaps before tax.

+ References

No definition available.

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- Definition

Other comprehensive income (loss) reclassification adjustment from AOCI for interest expense (income) on swaps, net of tax.

+ References

No definition available.

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- Definition

Other comprehensive income (loss) reclassification adjustment from AOCI for interest expense (income) on swaps, tax.

+ References

No definition available.

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- Definition

Other comprehensive income (loss) reclassification adjustment from AOCI for sale and for write down of securities and for net interest expense income on swaps, net of tax.

+ References

No definition available.

+ Details

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- Definition

Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized loss realized upon the write-down of available-for-sale securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-15

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-11

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 17A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-17A

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized loss realized upon the write-down of available-for-sale securities.

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- Definition

Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive income for unrealized loss realized upon the write-down of available-for-sale securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-12

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First Seacoast Bancorp, Inc. 10-Q