REVENUE RECOGNITION, Contract Liabilities - Customer Loyalty Programs (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Dec. 31, 2017
REVENUE RECOGNITION [Abstract]
Outstanding at beginning of period	[1]	$ 13,043
Increase (decrease) attributed to [Abstract]
Customer loyalty deferrals		2,090
Customer loyalty redemptions/expirations		(1,497)
Outstanding at end of period		$ 13,636
Loyalty point liability under cost provision methodology			$ 1,900

[1] The company recorded customer loyalty points under the cost provision method prior to the adoption of Topic 606. The loyalty point liability under the cost provision methodology was $1.9 million as of December 31, 2017. The Company recorded an additional liability of $11.2 million to the cumulative impact of adopting Topic 606.