LEASES - Supplemental Balance Sheet (Details) $ in Millions	Sep. 30, 2019 USD ($)
LEASES.
Operating lease right of use assets	$ 53.4
Financial position	us-gaap:OtherAssetsNoncurrent
Current operating leased liabilities	$ 8.8
Financial position	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Non-current operating lease liabilities	$ 47.4
Financial position	us-gaap:OperatingLeaseLiabilityNoncurrent
Total lease liabilities	$ 56.2
Financial position	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent us-gaap:OperatingLeaseLiabilityNoncurrent