Derivative Financial Instruments - Information about Fair Values of Derivative Instruments in Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$ 374,790	$ 435,969
Liability Derivatives, Fair Value	1,295,532	1,355,326
Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	13,176	4,239
Liability Derivatives, Fair Value	1,543	9,103
Fair Value Hedges [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	313,397	379,868
Liability Derivatives, Fair Value	1,253,627	1,300,184
Fair Value Hedges [Member] | Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	48,217	51,862
Liability Derivatives, Fair Value	40,362	46,039
Interest Rate Swap Agreements [Member] | Fair Value Hedges [Member] | Derivatives Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	3,631	1,202
Liability Derivatives, Fair Value	1,498	9,094
Commitments to Sell Real Estate Loans [Member] | Fair Value Hedges [Member] | Derivatives Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	45,080	51,410
Liability Derivatives, Fair Value	47	14
Commitments to Sell Real Estate Loans [Member] | Fair Value Hedges [Member] | Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	9,545	3,037
Liability Derivatives, Fair Value	45	9
Mortgage-Related Commitments to Originate Real Estate Loans for Sale [Member] | Fair Value Hedges [Member] | Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	3,137	452
Liability Derivatives, Fair Value	40,315	46,025
Interest Rate Contracts [Member] | Fair Value Hedges [Member] | Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	293,761	355,806
Liability Derivatives, Fair Value	1,234,889	1,278,180
Foreign Exchange and Other Option and Futures Contracts [Member] | Fair Value Hedges [Member] | Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	19,636	24,062
Liability Derivatives, Fair Value	$ 18,738	$ 22,004