ACQUISITIONS AND DIVESTITURES (Acquisitions- Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) DealershipLocations Franchises	Dec. 31, 2014 USD ($) DealershipLocations Franchises
Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Number of franchises acquired (in franchises) | Franchises	2	3
Number of dealership locations acquired (in dealership locations) | DealershipLocations	2	3
Aggregate purchase price	$ 69.4	$ 152.2
Cash paid for acquisition	52.7	106.5
Floor plan borrowings for puchase of related inventory	16.7	45.7
Cash held in escrow	$ 0.0	$ 6.9
Goodwill and manufacturer franchise rights, period for federal and state tax deductions	15 years
SOUTH CAROLINA [Member]
Business Acquisition [Line Items]
Number of franchises acquired (in franchises) | Franchises		1