Deposits - Schedule of Deposits (Detail) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Deposit [Line Items]
Non-interest-bearing demand deposits	$ 14,546,225	$ 14,143,815
Interest-bearing Domestic Deposit, Savings	9,888,997	10,457,328
Interest-bearing Domestic Deposit, Money Market	13,077,188	11,889,171
Interest-bearing Domestic Deposit, Time Deposits	6,709,961	6,427,550
Total interest-bearing deposit	29,676,146	28,774,049
Total deposits	$ 44,222,371	$ 42,917,864

Deposit [Line Items]

No definition available.

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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(12))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

+ Details

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- Definition

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

+ References

+ Details

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- Definition

Amount of interest-bearing domestic money market demand account deposit liabilities.

+ References

+ Details

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- Definition

Amount of interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity.

+ References

+ Details

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- Definition

Amount of interest-bearing domestic time deposits. Time deposits bear interest for a fixed, stated period of time and include certificate of deposits and individual retirement accounts.

+ References

+ Details

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- Definition

The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

+ References

+ Details

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