GOODWILL AND INTANGIBLE ASSETS Goodwill (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Goodwill	$ 667,159	$ 602,069
Gross Balance, December 31, 2016	1,075,135
Accumulated Impairment Losses, Beginning Balance	(473,066)
Foreign Currency	65,090
Accumulated Impairment Losses, Ending Balance	(473,066)
Gross Balance, June 30, 2017	1,140,225
BULGARIA [Member]
Goodwill [Roll Forward]
Goodwill	28,959	26,750
Gross Balance, December 31, 2016	171,389
Accumulated Impairment Losses, Beginning Balance	(144,639)
Foreign Currency	2,209
Accumulated Impairment Losses, Ending Balance	(144,639)
Gross Balance, June 30, 2017	173,598
CROATIA [Member]
Goodwill [Roll Forward]
Goodwill	594	534
Gross Balance, December 31, 2016	10,988
Accumulated Impairment Losses, Beginning Balance	(10,454)
Foreign Currency	60
Accumulated Impairment Losses, Ending Balance	(10,454)
Gross Balance, June 30, 2017	11,048
CZECH REPUBLIC [Member]
Goodwill [Roll Forward]
Goodwill	510,396	456,938
Gross Balance, December 31, 2016	744,483
Accumulated Impairment Losses, Beginning Balance	(287,545)
Foreign Currency	53,458
Accumulated Impairment Losses, Ending Balance	(287,545)
Gross Balance, June 30, 2017	797,941
ROMANIA [Member]
Goodwill [Roll Forward]
Goodwill	77,298	71,758
Gross Balance, December 31, 2016	82,786
Accumulated Impairment Losses, Beginning Balance	(11,028)
Foreign Currency	5,540
Accumulated Impairment Losses, Ending Balance	(11,028)
Gross Balance, June 30, 2017	88,326
SLOVAK REPUBLIC [Member]
Goodwill [Roll Forward]
Goodwill	49,912	46,089
Gross Balance, December 31, 2016	46,089
Accumulated Impairment Losses, Beginning Balance	0
Foreign Currency	3,823
Accumulated Impairment Losses, Ending Balance	0
Gross Balance, June 30, 2017	49,912
SLOVENIA [Member]
Goodwill [Roll Forward]
Goodwill	0	$ 0
Gross Balance, December 31, 2016	19,400
Accumulated Impairment Losses, Beginning Balance	(19,400)
Foreign Currency	0
Accumulated Impairment Losses, Ending Balance	(19,400)
Gross Balance, June 30, 2017	$ 19,400