Note 12 - Subordinated Debentures - Summary of Mandatory Redeemable Trust Preferred Securities (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023	Dec. 19, 2003
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	Secured Overnight Financing Rate (SOFR) [Member]	Secured Overnight Financing Rate (SOFR) [Member]
Subordinated Debt [Member] \| Center Bancorp Statutory Trust II [Member]
Securities issued	$ 5,000,000	$ 5,000,000	$ 5,000,000
Liquidation value (in dollars per share)	$ 1,000	$ 1,000
Coupon rate	2.85%	2.85%
Maturity	Jan. 23, 2034	Jan. 23, 2034
Redeemable by issuer beginning	Jan. 23, 2009	Jan. 23, 2009

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

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- Definition

Earliest date when the debt instrument can be converted into equity, in YYYY-MM-DD format.

+ References

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- Definition

Per share excess of preference in liquidation over convertible debt instrument's if-converted par or stated value of share.

+ References

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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- Definition

Indicates type of variable interest rate on debt instrument.

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