DISCONTINUED OPERATIONS, SIGNIFICANT DISPOSALS AND OTHER BUSINESS EXITS - Schedule of Assets and Liabilities (Details) - Discontinued Operations, Held-for-sale $ in Millions	Dec. 31, 2025 USD ($)
Poland Consumer Banking Business
Assets
Cash and deposits with banks	$ 4,700
Loans (net of allowance of $25000000 at December 31, 2025)	1,700
Other assets	54
Total assets	6,454
Liabilities
Deposits	6,144
Other liabilities	63
Total liabilities	6,207
Allowance	25
Deposits with banks	4,600
AO Citibank
Assets
Cash and deposits with banks	1,954
Other assets	10,616
Total assets	12,570
Liabilities
Deposits	12,742
Other liabilities	47
Total liabilities	12,789
AO Citibank \| Russia
Liabilities
Deposits	1,500
Reserve balance	$ 2,600

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