Percentage Of Amount Borrowed.

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Share based compensation arrangement by share based payment award equity instruments other than options grants in period grant date fair value.

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Stock Repurchase During Period Shares Esop

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The amount of plan compensation cost recognized during the period.

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Fair value of unearned shares held by the employee stock ownership plan (ESOP).

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The shares that, although not legally released, will be released by a future scheduled and committed debt service payment and will be allocated to employees for service rendered in the current accounting period. The ESOP documents typically define the period of service to which the shares relate. ESOP shares are released to compensate employees directly, to settle employer liabilities for other employee benefits, and to replace dividends on allocated shares that are used for debt service.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of noncash expense for share-based payment arrangement.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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Gross number of share options (or share units) granted during the period.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of new stock issued during the period.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Number of share options (or share units) exercised during the current period.

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Fair value of unearned shares for all classes of common stock and nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by an employee stock ownership plan (ESOP). Includes the sale of shares or the issuance treasury shares to an ESOP.

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Stock Based Compensation - Additional Information (Details) - USD ($)		3 Months Ended		12 Months Ended
	Nov. 18, 2021	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares committed to be released each year, ESOP		2,981	2,981	11,924
Unearned compensation for ESOP		$ 3,034,000		$ 3,163,000
Stock options granted, outstanding		0
Share price		$ 0
Income tax expense		$ 58,000	$ 256,000
Restricted Stock Awards [Member] \| Directors and Members [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award,	118,270,000
Share price		$ 9.99
Total fair value related to stock options granted		$ 1,200,000
Minimum [Member] \| Restricted Stock Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issued stock option granted, term		3 years
2021 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unearned compensation for ESOP		$ 1,000,000.0		$ 1,100,000
Common stock shares issued during period, new issues		417,327,000
Issued stock option granted, term		10 years
Share based expense recognized		$ 99,000
Income tax expense		$ 27,000,000
Weighted average future recognition period		2 years 7 months 6 days		2 years 10 months 24 days
2021 Equity Incentive Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Payment Arrangement, Exercise of Option		298,091,000
Stock Issued During Period, Shares, Restricted Stock Award,		119,236,000
First Seacoast Bank Employee Stock Ownership Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares committed to be released each year, ESOP		11,924
Employee stock option compensation recognized		$ 31,000,000,000	28,000,000,000
Unearned compensation for ESOP		2,000,000.0	$ 2,000,000.0
Employee stock option unallocated shares fair value		$ 2,100,000		$ 2,200,000
Employee stock option plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock repurchase		238,473
Percentage of purchase price common stock		100.00%
Remaining principal balance of debt		$ 2,100,000		$ 2,100,000