Derivative Financial Instruments (Narrative) (Detail)	3 Months Ended		6 Months Ended
	Dec. 31, 2022 USD ($) derivativeInstrument	Mar. 31, 2022 USD ($)	Jun. 30, 2023 USD ($) derivativeInstrument	Jun. 30, 2022 USD ($) derivativeInstrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount to be reclassified from accumulated other comprehensive income to interest income (expense) in the next twelve months			$ (68,900,000)
Net derivative liability position, aggregate fair value			0
Interest Rate Swap Terminated
Derivative Instruments, Gain (Loss) [Line Items]
Amount to be reclassified from accumulated other comprehensive income to interest income (expense) in the next twelve months			17,600,000
Interest Rate Swap And Collar
Derivative Instruments, Gain (Loss) [Line Items]
Amount to be reclassified from accumulated other comprehensive income to interest income (expense) in the next twelve months			(86,500,000)
Mortgage banking derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 190,000,000		$ 190,000,000
Number of derivative instruments held | derivativeInstrument	3		3
Not designated as hedging instrument | Interest rate contract
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount			$ 0
Not designated as hedging instrument | Interest rate contract terminated
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 1,000,000,000
Not designated as hedging instrument | Interest rate contract, qualified borrowers
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	9,600,000,000		11,200,000,000
Not designated as hedging instrument | Interest rate lock commitments
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	121,600,000		225,100,000
Not designated as hedging instrument | Forward commitments to sell mortgage loans
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	321,000,000		693,500,000
Not designated as hedging instrument | Commodity forward contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	3,600,000		6,600,000
Not designated as hedging instrument | Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 226,200,000		$ 205,300,000
Not designated as hedging instrument | Covered call options
Derivative Instruments, Gain (Loss) [Line Items]
Number of derivative instruments held | derivativeInstrument	0		0	0
Interest rate derivatives designated as Cash Flow Hedges | Designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount			$ 6,000,000,000
Interest rate derivatives designated as Cash Flow Hedges | Designated as hedging instrument | Interest Rate Swap Terminated
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount		$ 1,000,000,000		$ 500,000,000
Derivative term		5 years
Fair value of derivative contracts		$ 66,500,000
Number of derivative instruments held | derivativeInstrument				2
Interest rate derivatives designated as Cash Flow Hedges | Designated as hedging instrument | Interest Rate Swap Terminated, Original Swap Maturing March 2023
Derivative Instruments, Gain (Loss) [Line Items]
Fair value of derivative contracts				$ 3,700,000
Interest rate derivatives designated as Cash Flow Hedges | Designated as hedging instrument | Interest Rate Swap Terminated, Original Swap Maturing April 2024
Derivative Instruments, Gain (Loss) [Line Items]
Fair value of derivative contracts				$ 10,700,000
Interest rate derivatives designated as Cash Flow Hedges | Designated as hedging instrument | Interest Rate Collar Terminated
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 64,300,000
Fair value of derivative contracts	$ 875,000
Number of derivative instruments terminated | derivativeInstrument	1
Interest rate derivatives designated as Fair Value Hedges | Designated as hedging instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount			$ 204,100,000
Number of interest rate derivatives | derivativeInstrument			13