Derivative Financial Instruments (Schedule fair value of derivative instruments) (Detail) - USD ($)	Jun. 30, 2022	Dec. 31, 2021
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	$ 9,091,709,000	$ 5,554,015,000
Asset Derivatives, Fair Value, before netting	126,016,000	159,117,000
Asset Derivatives, Fair Value, Less: Master netting agreements	11,722,000	6,364,000
Asset Derivatives, Fair Value, Less: Cash collateral posted	89,220,000	19,272,000
Total derivative instruments, after netting	25,074,000	133,481,000
Liability Derivatives, Notional Amount	7,373,291,000	4,747,534,000
Liability Derivatives, Fair Value	212,551,000	21,784,000
Liability Derivatives, Fair Value, Less: Master netting agreements	11,722,000	6,364,000
Liability Derivatives, Fair Value, Less: Cash collateral posted	100,000	2,119,000
Total derivative instruments, after netting	200,729,000	13,301,000
CME
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value, Less: Cash collateral posted	70,300,000
Total derivative instruments, after netting	0
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	107,886,000	25,636,000
Asset Derivatives, Fair Value, Less: Master netting agreements	11,722,000	6,364,000
Total derivative instruments, after netting	89,220,000	19,272,000
Liability Derivatives, Fair Value	11,855,000	8,483,000
Liability Derivatives, Fair Value, Less: Master netting agreements	11,722,000	6,364,000
Total derivative instruments, after netting	100,000	2,119,000
Designated as Hedging Instrument | Interest rate derivatives
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	2,000,000,000	1,000,000,000
Asset Derivatives, Fair Value	3,843,000	17,583,000
Liability Derivatives, Notional Amount	500,000,000	0
Liability Derivatives, Fair Value	193,000	0
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	7,091,709,000	4,554,015,000
Asset Derivatives, Fair Value, Total	122,173,000	141,534,000
Liability Derivatives, Notional Amount	6,873,291,000	4,747,534,000
Liability Derivatives, Fair Value, Positions not subject to master netting agreement	212,358,000	21,784,000
Not Designated as Hedging Instrument | Interest rate derivatives
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	6,922,130,000	4,463,048,000
Asset Derivatives, Fair Value	121,351,000	141,243,000
Liability Derivatives, Notional Amount	6,390,965,000	4,372,846,000
Liability Derivatives, Fair Value	212,078,000	21,570,000
Not Designated as Hedging Instrument | Mortgage Banking Derivatives | RPA-Out
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	223,000	14,212,000
Asset Derivatives, Fair Value	2,000	80,000
Not Designated as Hedging Instrument | Mortgage Banking Derivatives | RPA-In
Derivatives, Fair Value [Line Items]
Liability Derivatives, Notional Amount	0	0
Liability Derivatives, Fair Value	0	0
Not Designated as Hedging Instrument | Other
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	169,356,000	76,755,000
Asset Derivatives, Fair Value	820,000	211,000
Liability Derivatives, Notional Amount	482,326,000	374,688,000
Liability Derivatives, Fair Value	280,000	214,000
Not Designated as Hedging Instrument | Interest Rate Swap, CME
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	2,700,000,000	400,000,000
Liability Derivatives, Notional Amount	400,000,000	2,600,000,000
Not Designated as Hedging Instrument | Credit Risk Contract | RPA-Out
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	131,700,000	66,000,000
Not Designated as Hedging Instrument | Credit Risk Contract | RPA-In
Derivatives, Fair Value [Line Items]
Liability Derivatives, Notional Amount	463,800,000	338,200,000
Interest Rate Lock Commitments
Derivatives, Fair Value [Line Items]
Other commitment	$ 200,000	$ 1,000,000