Loans and Leases Held for Investment, Net of Allowance For Loan and Lease Losses - Narrative (Detail) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest	$ 27.0	$ 15.6

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_InterestReceivable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant