DEPOSITS - Summary of Deposit Balances (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Deposits [Abstract]
Non-interest-bearing deposit accounts	$ 7,097,313	$ 4,546,123
Interest-bearing savings accounts	4,657,671	4,088,969
Interest-bearing checking accounts	3,550,456	3,651,806
Certificates of deposit	2,570,652	2,814,313
Brokered CD's	108,566	216,172
Total deposits	$ 17,984,658	$ 15,317,383

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.

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

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- Definition

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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- Definition

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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- Definition

Amount of interest-bearing domestic certificate of deposit liabilities.

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- Definition

Amount of interest-bearing domestic checking deposit liabilities.

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- Definition

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

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