RELATED PERSON TRANSACTIONS - Leased Property by Real Estate Ventures (Details) - President and Chief Executive Officer $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($) real_estate_venture	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) real_estate_venture	Sep. 30, 2016 USD ($)
Lease Services
Related Party Transaction [Line Items]
Payments for services (less than)	$ 0.1	$ 0.1	$ 0.1	$ 0.1
Real estate ventures in Baltimore, MD | Lease Services
Related Party Transaction [Line Items]
Number of consolidated real estate ventures | real_estate_venture	1		1
Real estate ventures in Towson, MD | Lease Services
Related Party Transaction [Line Items]
Number of consolidated real estate ventures | real_estate_venture	1		1
Annual rent			$ 0.1	0.2
Maximum | Real estate ventures in Baltimore, MD | Lease Services
Related Party Transaction [Line Items]
Amount received	$ 0.1	$ 0.2	$ 0.3	$ 0.5