Deposits - Schedule of Deposits (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Deposit [Line Items]
Non-interest-bearing demand deposits	$ 18,114,430	$ 18,423,018
Interest-bearing Domestic Deposit, Savings	12,484,308	11,930,959
Interest-bearing Domestic Deposit, Money Market	12,490,612	11,228,815
Interest-bearing Domestic Deposit, Time Deposits	1,341,579	1,112,904
Interest-bearing deposits	26,316,499	24,272,678
Deposits	$ 44,430,929	$ 42,695,696

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

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Balance Type:	credit
Period Type:	instant

- 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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Data Type:	xbrli:monetaryItemType
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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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Data Type:	xbrli:monetaryItemType
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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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Data Type:	xbrli:monetaryItemType
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