Loans and Leases Held for Investment, Net of Allowance For Loan and Lease Losses - Nonaccrual and Past Due Table (Details) $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($)
Financing Receivable, Past Due [Line Items]
Nonaccrual	$ 11,976
Nonaccrual with no related ACL	$ 4,774
Nonaccrual Ratios	0.40%
Allowance for loan and lease losses to nonaccrual loans and leases, percent	875.00%
Nonaccuring Loans And Leases, Excluding PPP Loans \| Loans And Leases, Class \| Credit Concentration Risk
Financing Receivable, Past Due [Line Items]
Concentration risk, percentage	0.50%
Consumer Portfolio Segment
Financing Receivable, Past Due [Line Items]
Nonaccrual	$ 8,598
Nonaccrual with no related ACL	$ 2,488
Nonaccrual Ratios	0.50%
Consumer Portfolio Segment \| Unsecured personal
Financing Receivable, Past Due [Line Items]
Nonaccrual	$ 604
Nonaccrual with no related ACL	0
Consumer Portfolio Segment \| Residential mortgages
Financing Receivable, Past Due [Line Items]
Nonaccrual	2,106
Nonaccrual with no related ACL	2,106
Consumer Portfolio Segment \| Secured consumer
Financing Receivable, Past Due [Line Items]
Nonaccrual	5,888
Nonaccrual with no related ACL	382
Consumer Portfolio Segment \| Other consumer
Financing Receivable, Past Due [Line Items]
Nonaccrual	0
Nonaccrual with no related ACL	0
Commercial Portfolio Segment
Financing Receivable, Past Due [Line Items]
Nonaccrual	3,378
Nonaccrual with no related ACL	$ 2,286
Nonaccrual Ratios	0.30%
Commercial Portfolio Segment \| Equipment finance
Financing Receivable, Past Due [Line Items]
Nonaccrual	$ 744
Nonaccrual with no related ACL	0
Commercial Portfolio Segment \| Commercial real estate
Financing Receivable, Past Due [Line Items]
Nonaccrual	1,219
Nonaccrual with no related ACL	1,219
Commercial Portfolio Segment \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
Nonaccrual	1,415
Nonaccrual with no related ACL	$ 1,067

Percentage of allowance for credit loss to nonaccrual financing receivable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (3)

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