Deposits (Summary Of Deposits) (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Non-interest-bearing:
Demand	$ 4,883,436	$ 4,446,463
Interest-bearing:
HSA	6,736,178	6,416,135
Checking	3,007,069	2,689,734
Money market	2,477,304	2,312,840
Savings	4,418,689	4,354,809
Time deposits	2,991,161	3,104,765
Total interest-bearing	19,630,401	18,878,283
Total deposits	24,513,837	23,324,746
Time deposits and interest-bearing checking, included in above balances, obtained through brokers	810,190	652,151
Time deposits, included in above balance, that exceed the FDIC limit	588,488	661,334
Deposit overdrafts reclassified as loan balances	$ 1,358	$ 1,721

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=6876686&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
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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=6876686&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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