Investment Securities - Summary Of Debt Securities Held-to Maturity - Contractual Maturities, Credit Quality and Other Information (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Amortized Cost
Maturing within 1 year	$ 2,902
After 1 year through 5 years	160,194
After 5 through 10 years	286,121
After 10 years	7,743,605
Amortized Cost	8,192,822	$ 8,444,362
Fair Value
Maturing within 1 year	2,903
After 1 year through 5 years	154,188
After 5 through 10 years	275,974
After 10 years	6,858,179
Fair Value	$ 7,291,244	$ 7,453,123

Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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