REGULATORY CAPITAL - Subsidiaries with Regulatory Capital Requirements (Details) $ in Millions	Dec. 31, 2025 USD ($)
Cboe Trading
Regulatory Capital Requirement [Line Items]
Actual	$ 16.9
Minimum Requirement	0.8
BIDS Trading
Regulatory Capital Requirement [Line Items]
Actual	11.7
Minimum Requirement	0.2
Cboe Fixed Income
Regulatory Capital Requirement [Line Items]
Actual	2.4
Minimum Requirement	0.1
Cboe Europe
Regulatory Capital Requirement [Line Items]
Actual	71.2
Minimum Requirement	36.6
Cboe Chi-X Europe
Regulatory Capital Requirement [Line Items]
Actual	0.1
Minimum Requirement	0.1
Cboe Clear Europe
Regulatory Capital Requirement [Line Items]
Actual	128.1
Minimum Requirement	76.0
CFE
Regulatory Capital Requirement [Line Items]
Actual	104.5
Minimum Requirement	40.3
Cboe SEF
Regulatory Capital Requirement [Line Items]
Actual	10.8
Minimum Requirement	2.5
Cboe Digital Exchange
Regulatory Capital Requirement [Line Items]
Actual	21.6
Minimum Requirement	0.0
Cboe Clear U.S.
Regulatory Capital Requirement [Line Items]
Actual	35.1
Minimum Requirement	12.1
Cboe Australia
Regulatory Capital Requirement [Line Items]
Actual	17.9
Minimum Requirement	5.9
Cboe Japan
Regulatory Capital Requirement [Line Items]
Actual	6.8
Minimum Requirement	4.6
Cboe NL
Regulatory Capital Requirement [Line Items]
Actual	21.1
Minimum Requirement	$ 10.3