ACCRUED EXPENSES AND OTHER (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accrued expenses and other [Abstract]
Employee compensation and benefits	$ 427.6	$ 369.3
Self-insurance reserves	40.4	45.7
Accrued taxes payable	124.8	70.6
Royalty and license fees payable	6.4	6.2
Accrued investigator fees and pass through costs	80.4	71.6
Restructuring reserves	19.8	22.0
Acquisition related reserves	19.7	21.3
Interest payable	70.7	71.7
Other Accrued Liabilities	26.0	24.6
Other	54.2	90.3
Total accrued expenses and other	$ 870.0	$ 793.3