Loans and Leases Held for Investment at Amortized Cost, Net of Allowance For Loan and Lease Losses - Nonaccrual and Past Due Table (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Past Due [Line Items]
Nonaccrual	$ 44,382	$ 34,827
Nonaccrual with no related ACL	$ 4,089	$ 2,617
Nonaccrual ratios	0.90%	0.70%
Consumer Portfolio Segment
Financing Receivable, Past Due [Line Items]
Nonaccrual	$ 30,661	$ 16,774
Nonaccrual with no related ACL	$ 312	$ 331
Nonaccrual ratios	0.70%	0.40%
Consumer Portfolio Segment \| Unsecured personal
Financing Receivable, Past Due [Line Items]
Nonaccrual	$ 30,132	$ 16,255
Nonaccrual with no related ACL	0	0
Consumer Portfolio Segment \| Residential mortgages
Financing Receivable, Past Due [Line Items]
Nonaccrual	312	331
Nonaccrual with no related ACL	312	331
Consumer Portfolio Segment \| Secured consumer
Financing Receivable, Past Due [Line Items]
Nonaccrual	217	188
Nonaccrual with no related ACL	0	0
Commercial Portfolio Segment
Financing Receivable, Past Due [Line Items]
Nonaccrual	13,721	18,053
Nonaccrual with no related ACL	$ 3,777	$ 2,286
Nonaccrual ratios	2.00%	2.30%
Commercial Portfolio Segment \| Loans guaranteed by the Small Business Association
Financing Receivable, Past Due [Line Items]
Nonaccrual	$ 10,400	$ 4,900
Commercial Portfolio Segment \| Equipment finance
Financing Receivable, Past Due [Line Items]
Nonaccrual	0	898
Nonaccrual with no related ACL	0	39
Commercial Portfolio Segment \| Commercial real estate
Financing Receivable, Past Due [Line Items]
Nonaccrual	9,663	1,018
Nonaccrual with no related ACL	2,187	1,018
Commercial Portfolio Segment \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
Nonaccrual	4,058	16,137
Nonaccrual with no related ACL	$ 1,590	$ 1,229

Percentage of nonaccrual to total financing receivable outstanding.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)
-Publisher SEC

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Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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