SEGMENT REPORTING - Geographic and Narratives (Details) $ in Millions	12 Months Ended
Dec. 31, 2025 USD ($) segment	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
SEGMENT REPORTING
Number of reportable segments \| segment	2
Financial information by reportable operating segment
Revenues	$ 4,848.9	$ 4,637.2	$ 4,812.6
Long-term assets, net	7,287.3	7,300.3
U. S. markets \| Operating Segments
Financial information by reportable operating segment
Long-term assets, net	5,267.4	5,474.2
International markets \| Operating Segments
Financial information by reportable operating segment
Long-term assets, net	2,019.9	1,826.1
U.S. Markets
Financial information by reportable operating segment
Revenues	3,706.1	3,544.2	3,688.7
UK
Financial information by reportable operating segment
Revenues	428.5	408.8	400.9
Spain
Financial information by reportable operating segment
Revenues	153.4	143.3	148.2
Sweden
Financial information by reportable operating segment
Revenues	122.5	116.4	124.9
Italy
Financial information by reportable operating segment
Revenues	147.3	147.6	151.9
Germany
Financial information by reportable operating segment
Revenues	124.3	111.6	125.8
Finland
Financial information by reportable operating segment
Revenues	84.7	90.1	97.9
Ireland
Financial information by reportable operating segment
Revenues	33.1	32.5	32.2
Other foreign countries
Financial information by reportable operating segment
Revenues	$ 49.0	$ 42.7	$ 42.1

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