LEASES - Maturities of lease liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Lease liabilites
2020	$ 38.4
2021	39.6
2022	38.6
2023	36.8
2024	35.6
Thereafter	237.4
Total undiscounted lease liabilities	426.4
Less: Amount representing interest	(112.1)
Total present value of minimum lease payments	314.3
Amounts recognized in the December 31, 2019 consolidated balance sheet:
Current operating lease liabilities	22.6
Long-term operating lease liabilities	291.7
Total present value of minimum lease payments	$ 314.3
Operating Leases - Future Minimum Payments
2019		$ 42.0
2020		39.9
2021		37.7
2022		36.8
2023		35.6
Thereafter		256.4
Total		$ 448.4

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