RELATED PERSON TRANSACTIONS - Atlantic Automotive Corporation (Details) - Atlantic Automotive Corporation - Affiliated Entity $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($) real_estate_venture	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) real_estate_venture	Jun. 30, 2016 USD ($)
Lease Services
Related Party Transaction [Line Items]
Annual rent	$ 0.1	$ 0.2	$ 0.4	$ 0.5
Lease Services | Real estate ventures in Towson, MD
Related Party Transaction [Line Items]
Number of consolidated real estate ventures | real_estate_venture	1		1
Maximum | Advertising time
Related Party Transaction [Line Items]
Amount received	$ 0.2	$ 0.2	$ 0.3	$ 0.2