Deposits (Summary Of Deposits) (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Non-interest-bearing:
Demand	$ 13,570,702	$ 7,060,488
Interest-bearing:
HSA	7,804,858	7,397,582
Checking	9,579,839	4,182,497
Money market	11,964,649	3,718,953
Savings	8,615,138	5,689,739
Time deposits	2,821,097	1,797,770
Total interest-bearing	40,785,581	22,786,541
Total deposits	54,356,283	29,847,029
Time deposits, money market, and interest-bearing checking obtained through brokers	115,538	120,392
Aggregate amount of time deposit accounts that exceeded the FDIC limit	390,023	256,522
Demand deposit overdrafts reclassified as loan balances	$ 10,122	$ 1,577

Amount of deposits held by the entity that have been reclassified as loan balances receivable, for example, but not limited to, overdrafts receivable.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116652737&loc=d3e64164-112818

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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-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

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Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

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Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

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

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Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

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Amount of interest-bearing domestic checking deposit liabilities.

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Amount of other interest-bearing domestic deposit liabilities.

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

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Amount of time deposit liabilities, including certificates of deposit.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 405
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-URI http://asc.fasb.org/extlink&oid=116652737&loc=d3e64164-112818

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

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