Revenue from Contracts with Customers - Summary of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	$ 5,538	$ 12,095	$ 12,363	$ 19,929
Bank-owned life insurance income	636	348	1,190	692
Gain on sale of securities	0	0	108	0
Other noninterest income	501	763	655	2,273
Total noninterest income	6,675	13,206	14,316	22,894
Within Scope
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	5,538	12,095	12,363	19,929
Other noninterest income	501	763	655	2,273
Total noninterest income	6,039	12,858	13,018	22,202
Out of Scope
Disaggregation of Revenue [Line Items]
Bank-owned life insurance income	636	348	1,190	692
Gain on sale of securities			108
Total noninterest income	636	348	1,298	692
BM Tech
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	5,239	11,474	11,769	18,637
Bank-owned life insurance income	0	0	0	0
Gain on sale of securities			0
Other noninterest income	300	1	300	1,401
Total noninterest income	5,539	11,475	12,069	20,038
Community Banking
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	299	621	594	1,292
Bank-owned life insurance income	636	348	1,190	692
Gain on sale of securities			108
Other noninterest income	201	762	355	872
Total noninterest income	1,136	1,731	2,247	2,856
Interchange and card revenue
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	1,673	2,164	3,894	4,170
Interchange and card revenue \| Within Scope
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	1,673	2,164	3,894	4,170
Interchange and card revenue \| BM Tech
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	1,673	1,844	3,894	3,463
Interchange and card revenue \| Community Banking
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	0	320	0	707
Servicing fees
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts		5,764		8,190
Servicing fees \| Within Scope
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts		5,764		8,190
Servicing fees \| BM Tech
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts		5,764		8,190
Servicing fees \| Community Banking
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts		0		0
Service charges
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	1,990	2,396	4,272	4,385
Service charges \| Within Scope
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	1,990	2,396	4,272	4,385
Service charges \| BM Tech
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	1,691	2,095	3,678	3,800
Service charges \| Community Banking
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	299	301	594	585
University fees - transaction activity
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	518	430	1,452	952
University fees - transaction activity \| Within Scope
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	518	430	1,452	952
University fees - transaction activity \| BM Tech
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	518	430	1,452	952
University fees - transaction activity \| Community Banking
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	0	0	0	0
University fees - subscriptions
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	1,357	1,341	2,745	2,232
University fees - subscriptions \| Within Scope
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	1,357	1,341	2,745	2,232
University fees - subscriptions \| BM Tech
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	1,357	1,341	2,745	2,232
University fees - subscriptions \| Community Banking
Disaggregation of Revenue [Line Items]
Total service charges on deposit accounts	$ 0	$ 0	$ 0	$ 0

Earnings on or other increases in the value of the cash surrender value of bank owned life insurance policies.

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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