ACQUISITIONS (Details) $ / shares in Units, shares in Millions, $ in Millions	Apr. 06, 2022 USD ($) branch $ / shares shares	Feb. 18, 2022 USD ($) branch	Mar. 31, 2022 USD ($)	Jul. 28, 2021 $ / shares
80 Branches And Deposit Business, HSBC Bank
Business Acquisition [Line Items]
Deposits		$ 6,300
Loans receivable, net		1,500
Estimated increase in goodwill		$ 120
80 Branches And Deposit Business, HSBC Bank | New York City Metro
Business Acquisition [Line Items]
Number of branches acquired | branch		66
80 Branches And Deposit Business, HSBC Bank | Mid-Atlantic/Washington D.C.
Business Acquisition [Line Items]
Number of branches acquired | branch		9
80 Branches And Deposit Business, HSBC Bank | Southeast Florida
Business Acquisition [Line Items]
Number of branches acquired | branch		5
Investor Acquisition
Business Acquisition [Line Items]
Deposits			$ 20,000
Loans receivable, net			$ 23,000
Investor Acquisition | Subsequent Event
Business Acquisition [Line Items]
Number of branches acquired | branch	154
Number of shares issued for acquisition | shares	73.6
Amount paid to shareholders of Investors	$ 355
Cash consideration, in dollars per share for each share of investors stock (in dollars per share) | $ / shares	$ 1.46
Investor Acquisition | Common Stock
Business Acquisition [Line Items]
Stock consideration (in dollars per each share) | $ / shares				$ 0.297