LONG-TERM OBLIGATIONS - Fees and Rates Under Credit Facilities (Details)	12 Months Ended
	Dec. 31, 2018
Consolidated Leverage Ratio: Greater Than 3.00 to 1.0
Line of Credit Facility [Line Items]
Commitment Fee	0.35%
Letter of Credit Fee	2.00%
Consolidated Leverage Ratio: Greater Than 3.00 to 1.0 | Minimum [Member]
Line of Credit Facility [Line Items]
Consolidated Leverage Ratio	3.00
Consolidated Leverage Ratio: Greater Than 3.00 to 1.0 | Base Rate [Member]
Line of Credit Facility [Line Items]
Margin on Loans	1.25%
Consolidated Leverage Ratio: Greater Than 3.00 to 1.0 | Eurodollar [Member]
Line of Credit Facility [Line Items]
Margin on Loans	2.25%
Consolidated Leverage Ratio: Less Than Equal To 3.00 to 1.0 but Greater Than 2.00 to 1.0
Line of Credit Facility [Line Items]
Commitment Fee	0.30%
Letter of Credit Fee	1.75%
Consolidated Leverage Ratio: Less Than Equal To 3.00 to 1.0 but Greater Than 2.00 to 1.0 | Maximum [Member]
Line of Credit Facility [Line Items]
Consolidated Leverage Ratio	3.00
Consolidated Leverage Ratio: Less Than Equal To 3.00 to 1.0 but Greater Than 2.00 to 1.0 | Minimum [Member]
Line of Credit Facility [Line Items]
Consolidated Leverage Ratio	2.00
Consolidated Leverage Ratio: Less Than Equal To 3.00 to 1.0 but Greater Than 2.00 to 1.0 | Base Rate [Member]
Line of Credit Facility [Line Items]
Margin on Loans	1.00%
Consolidated Leverage Ratio: Less Than Equal To 3.00 to 1.0 but Greater Than 2.00 to 1.0 | Eurodollar [Member]
Line of Credit Facility [Line Items]
Margin on Loans	2.00%
Consolidated Leverage Ratio: Less Than Equal To 2.00 to 1.0 but Greater Than 1.00 to 1.0
Line of Credit Facility [Line Items]
Commitment Fee	0.25%
Letter of Credit Fee	1.50%
Consolidated Leverage Ratio: Less Than Equal To 2.00 to 1.0 but Greater Than 1.00 to 1.0 | Maximum [Member]
Line of Credit Facility [Line Items]
Consolidated Leverage Ratio	2.00
Consolidated Leverage Ratio: Less Than Equal To 2.00 to 1.0 but Greater Than 1.00 to 1.0 | Minimum [Member]
Line of Credit Facility [Line Items]
Consolidated Leverage Ratio	1.00
Consolidated Leverage Ratio: Less Than Equal To 2.00 to 1.0 but Greater Than 1.00 to 1.0 | Base Rate [Member]
Line of Credit Facility [Line Items]
Margin on Loans	0.75%
Consolidated Leverage Ratio: Less Than Equal To 2.00 to 1.0 but Greater Than 1.00 to 1.0 | Eurodollar [Member]
Line of Credit Facility [Line Items]
Margin on Loans	1.75%
Consolidated Leverage Ratio: Less Than Equal To 1.00 to 1.0
Line of Credit Facility [Line Items]
Commitment Fee	0.20%
Letter of Credit Fee	1.25%
Consolidated Leverage Ratio: Less Than Equal To 1.00 to 1.0 | Maximum [Member]
Line of Credit Facility [Line Items]
Consolidated Leverage Ratio	1.00
Consolidated Leverage Ratio: Less Than Equal To 1.00 to 1.0 | Base Rate [Member]
Line of Credit Facility [Line Items]
Margin on Loans	0.50%
Consolidated Leverage Ratio: Less Than Equal To 1.00 to 1.0 | Eurodollar [Member]
Line of Credit Facility [Line Items]
Margin on Loans	1.50%