FAIR VALUE MEASUREMENT - Fair Value Hierarchy of Financial Instruments Held (Details) - Fair Value, Nonrecurring - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Assets:
Deferred compensation plan assets	$ 35.4	$ 35.8
Digital assets held	0.4
Total assets	1,481.1	1,578.3
Liabilities:
Deferred compensation plan liabilities	35.4	35.8
Debt	1,361.5	1,371.8
Total liabilities	1,396.9	1,407.6
US Treasury Securities
Assets:
U.S. Treasury securities	0.5	0.3
US And UK Treasury securities
Assets:
Cash and cash equivalents	1,205.7	1,294.1
Money market funds
Assets:
Cash and cash equivalents	239.1	248.1
Level 1
Assets:
Deferred compensation plan assets	35.4	35.8
Digital assets held	0.0
Total assets	1,480.7	1,578.3
Liabilities:
Deferred compensation plan liabilities	35.4	35.8
Debt	0.0	0.0
Total liabilities	35.4	35.8
Level 1 | US Treasury Securities
Assets:
U.S. Treasury securities	0.5	0.3
Level 1 | US And UK Treasury securities
Assets:
Cash and cash equivalents	1,205.7	1,294.1
Level 1 | Money market funds
Assets:
Cash and cash equivalents	239.1	248.1
Level 2
Assets:
Deferred compensation plan assets	0.0	0.0
Digital assets held	0.4
Total assets	0.4	0.0
Liabilities:
Deferred compensation plan liabilities	0.0	0.0
Debt	1,361.5	1,371.8
Total liabilities	1,361.5	1,371.8
Level 2 | US Treasury Securities
Assets:
U.S. Treasury securities	0.0	0.0
Level 2 | US And UK Treasury securities
Assets:
Cash and cash equivalents	0.0	0.0
Level 2 | Money market funds
Assets:
Cash and cash equivalents	0.0	0.0
Level 3
Assets:
Deferred compensation plan assets	0.0	0.0
Digital assets held	0.0
Total assets	0.0	0.0
Liabilities:
Deferred compensation plan liabilities	0.0	0.0
Debt	0.0	0.0
Total liabilities	0.0	0.0
Level 3 | US Treasury Securities
Assets:
U.S. Treasury securities	0.0	0.0
Level 3 | US And UK Treasury securities
Assets:
Cash and cash equivalents	0.0	0.0
Level 3 | Money market funds
Assets:
Cash and cash equivalents	$ 0.0	$ 0.0