SHAREHOLDERS' EQUITY, Narrative (Details) $ / shares in Units, $ in Millions			3 Months Ended
	Jun. 01, 2022 USD ($) $ / shares shares	Sep. 21, 2021	Sep. 30, 2021 USD ($) $ / shares shares	Jun. 30, 2022 USD ($) $ / shares shares	Mar. 31, 2022 $ / shares shares	Dec. 31, 2021 USD ($) shares
Class of Stock [Line Items]
Preferred stock, par value per share (in usd per share) | $ / shares					$ 0.10
Preferred stock, value issued | $			$ 0	$ 120
Share repurchases, authorized amount | $						$ 1,000
Shares repurchased (in shares)	1,140,000
Shares repurchased | $	$ 100
Shares repurchased (in usd per share) | $ / shares	$ 88
Share repurchases, remaining authorized amount | $				$ 900
Stock split ratio		1.5	1.5
Stock dividend percent		50.00%
Capital stock, shares authorized (in shares)					660,000,000	360,000,000
Common stock, shares authorized (in shares)			350,000,000	650,000,000	650,000,000
Common stock, par value per share (in usd per share) | $ / shares			$ 0.01	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)					10,000,000
TriState Capital
Class of Stock [Line Items]
Shares issued (in shares)	7,970,000
Restricted stock awards (in shares)	551,000
Series A Depositary Shares
Class of Stock [Line Items]
Issuance of shares (in shares)	1,610,000
Depositary shares ratio	0.025
Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock percentage	6.75%
Preferred stock, par value per share (in usd per share) | $ / shares	$ 0.10
Preferred stock, liquidation preference (in usd per share) | $ / shares	1,000
Depositary shares, liquidation preference (in usd per share) | $ / shares	$ 25
Preferred stock, shares issued (in shares)				40,250
Preferred stock, shares outstanding (in shares)				40,250
Preferred stock, value issued | $				$ 41
Preferred stock, aggregate liquidation preference | $				$ 40
Series A Preferred Stock | London Interbank Offered Rate (LIBOR)
Class of Stock [Line Items]
Spread on variable rate	3.985%
Series B Depositary Shares
Class of Stock [Line Items]
Issuance of shares (in shares)	3,220,000
Depositary shares ratio	0.025
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock percentage	6.375%
Preferred stock, par value per share (in usd per share) | $ / shares	$ 0.10
Preferred stock, liquidation preference (in usd per share) | $ / shares	1,000
Depositary shares, liquidation preference (in usd per share) | $ / shares	$ 25
Preferred stock, shares issued (in shares)				80,500
Preferred stock, shares outstanding (in shares)				80,500
Preferred stock, value issued | $				$ 79
Preferred stock, aggregate liquidation preference | $				$ 81
Series B Preferred Stock | London Interbank Offered Rate (LIBOR)
Class of Stock [Line Items]
Spread on variable rate	4.088%