Reporting Segments and Related Information - Narrative (Detail) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($) segment	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Segment Reporting [Abstract]
Number of client-focused reportable segment \| segment	2
Segment reporting information, fully taxable-equivalent adjustment \| $	$ 45.6	$ 35.6	$ 34.4

Represents Fully Taxable-Equivalent Adjustment (FTE). Net interest income stated on an FTE basis is a non-GAAP financial measure that facilitates the analysis of asset yields and provides a clearer indication of net interest margins for comparative purposes.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration