Securities - Contractual Maturity Information for Securities Held to Maturity (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Investments Debt And Equity Securities [Abstract]
Due in 1 year or less, Amortized Cost	$ 55,797
Due after 1 year through 5 years, Amortized Cost	341,617
Due after 5 years through 10 years, Amortized Cost	720,150
Due after 10 years, Amortized Cost	1,503,163
Total, Amortized cost	2,620,727
Mortgage-backed securities, Amortized cost	3,088,814
Amortized Cost	5,709,541	$ 1,480,416
Due in 1 year or less, Fair Value	55,397
Due after 1 year through 5 years, Fair Value	333,267
Due after 5 years through 10 years, Fair Value	654,860
Due after 10 years, Fair Value	1,325,912
Total, Fair value	2,369,436
Mortgage-backed securities, Fair value	2,876,015
Total securities held to maturity, Fair value	$ 5,245,451	$ 1,442,391

Mortgage backed securities held to maturity amortized cost.

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

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as held-to-maturity.

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