LEASES - Adoption of New Accounting Standard (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Jan. 01, 2019
LEASE
Right-of-use assets	$ 95.9
Net lease liabilities	$ 105.1
Elect the hindsight practical expedient related to lease term and impairment	true
Adopt the land easement practical expedient	true
Lessee, Operating Lease, Existence of Option to Extend [true false]	true
Lessee, Finance Lease, Existence of Option to Extend [true false]	true
Lessee, Operating Lease, Existence of Option to Terminate [true false]	true
Lessee, Finance Lease, Existence of Option to Terminate [true false]	true
Finance lease right-of-use assets	$ 25.3
Impairment charge to right-of-use assets relating to operating leases	10.0
Impairment charge to right-of-use assets relating to finance leases	$ 0.8
Maximum
LEASE
Lease, renewal terms	5 years
Maximum | Revenue equipment
LEASE
Finance Lease, initial terms	9 years
Maximum | Real estate
LEASE
Operating lease, initial terms	15 years
Minimum
LEASE
Number of lease renewal options	one
Lease, renewal terms	1 year
Minimum | Revenue equipment
LEASE
Operating lease, initial terms	12 months
Finance Lease, initial terms	3 years
Minimum | Real estate
LEASE
Operating lease, initial terms	3 years
Accounting Standards Update 2016-02
LEASE
Right-of-use assets		$ 96.9
Net lease liabilities		$ 96.9