Loans and Allowance for Credit Losses on Loans - Summary of Credit Quality Indicators for Student Loans (Details) $ in Thousands	Jun. 30, 2026 USD ($) Loan	Dec. 31, 2025 USD ($) Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Loans | Loan	504	0
Principal Amount	$ 3,543,273	$ 2,540,570
School
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Loans | Loan	14	0
Grace
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Loans | Loan	9	0
Repayment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Loans | Loan	304	0
Deferment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Loans | Loan	75	0
Forbearance
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Loans | Loan	102	0
Consumer:
Financing Receivable, Recorded Investment, Past Due [Line Items]
Principal Amount	$ 448,282	$ 415,350
Consumer: | Student Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Principal Amount	24,237	0
Accrued Interest	2,456	0
Consumer: | Student Loans | School
Financing Receivable, Recorded Investment, Past Due [Line Items]
Principal Amount	398	0
Accrued Interest	360	0
Consumer: | Student Loans | Grace
Financing Receivable, Recorded Investment, Past Due [Line Items]
Principal Amount	244	0
Accrued Interest	221	0
Consumer: | Student Loans | Repayment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Principal Amount	14,629	0
Accrued Interest	201	0
Consumer: | Student Loans | Deferment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Principal Amount	3,844	0
Accrued Interest	984	0
Consumer: | Student Loans | Forbearance
Financing Receivable, Recorded Investment, Past Due [Line Items]
Principal Amount	5,122	0
Accrued Interest	$ 690	$ 0