Loans Receivable and Allowance for Credit Losses - Narrative (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($) loan	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) loan	Sep. 30, 2023 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($) loan	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale	$ 0		$ 0			$ 0
Gain on sale of loans held-for-sale	459,000	$ 455,000	825,000	$ 1,400,000
Loss on sale of loans held-for-sale	0	58,000	0	383,000
Purchases of loans receivable	0	0	0	14,729,000
Loans receivable	7,857,190,000		7,857,190,000			7,874,537,000
Carrying value of servicing liability	$ 513,000,000.0		$ 513,000,000.0			$ 551,000,000.0
Threshold period, past due status of financial receivables			30 days
Threshold period, past due for nonperforming status of financial receivables	90 days		90 days			90 days
Non-accrual	$ 28,000,000.0		$ 28,000,000.0			$ 12,600,000
Financing receivable, excluding accrued interest, 90 days or more past due, still accruing	0		0			0
Real estate owned	2,000,000.0		2,000,000.0			0
Accrued interest receivable on loans receivable	33,600,000		33,600,000			32,900,000
Specific Allowance	0		0			614,000
Impaired loans for which there are no related allowance for loan losses	32,792,000		32,792,000			19,919,000
Off-balance sheet, credit loss, liability	3,440,000	5,810,000	3,440,000	5,810,000	$ 3,988,000	5,484,000	$ 6,330,000	$ 6,970,000
(Reversal of) provision for credit losses	(548,000)	(520,000)	(2,044,000)	(1,160,000)
Stewardship Financial Corporation | Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,200,000		1,200,000			1,700,000
Freehold Entities | Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	247,000		247,000			2,800,000
RSI Entites | Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	10,400,000		10,400,000			10,600,000
Less Than 90 Days
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual	$ 23,600,000		$ 23,600,000			$ 1,600,000
Financial receivable, number of loans in nonaccrual status | loan	32		32			10
Commercial business loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales of loans held-for-sale			$ 6,800,000
Specific Allowance	$ 0		0			$ 154,000
Impaired loans for which there are no related allowance for loan losses	12,062,000		12,062,000			5,814,000
Commercial business loans | Paycheck Protection Program
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	530,000		530,000			809,000
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales of loans held-for-sale	2,800,000	7,100,000		18,400,000
Commercial real estate | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales of loans held-for-sale		1,900,000	2,700,000	5,700,000
Commercial real estate | One-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales of loans held-for-sale	$ 6,200,000	$ 6,800,000	$ 6,400,000	64,600,000
Mortgage loans in process of foreclosure, number of loans | loan	4		4
Mortgage loans in process of foreclosure, amount	$ 1,200,000		$ 1,200,000
Specific Allowance	0		0			186,000
Impaired loans for which there are no related allowance for loan losses	7,238,000		7,238,000			$ 1,170,000
Commercial real estate | Home equity loans and advances
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales of loans held-for-sale				$ 21,400,000
Consumer loans | Home equity loans and advances
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans in process of foreclosure, number of loans | loan						1
Mortgage loans in process of foreclosure, amount						$ 93,000
Specific Allowance	0		0			30,000
Impaired loans for which there are no related allowance for loan losses	$ 171,000		$ 171,000			$ 145,000
Consumer loans | Residential Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans in process of foreclosure, number of loans | loan						1
Mortgage loans in process of foreclosure, amount						$ 576,000