QUARTERLY FINANCIAL DATA (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Data [Abstract]
Net revenues	$ 196,154	$ 119,431	$ 146,895	$ 111,732		$ 107,527	$ 142,803	$ 105,817	$ 574,212	$ 526,174	$ 496,195
Cost of revenues	103,853	77,606	80,081	77,968		73,276	80,691	77,125	339,508	324,388	316,618
Operating income	57,750	16,022	43,153	13,024		11,450	39,718	8,903	129,949	105,532	88,047
(Loss) / income from continuing operations	36,715	(1,945)	25,265	(5,982)		(11,769)	(139,148)	(34,878)	54,053	(164,425)	(86,176)
(Loss) / income from discontinued operations, net of tax	4,121	(5,988)	2,533	(5,292)		(8,054)	(2,101)	(5,816)	(4,626)	(16,172)	(29,396)
Net (loss) / income	40,836	(7,933)	27,798	(11,274)		(19,823)	(141,249)	(40,694)	49,427	(180,597)	(115,572)
Net (loss) / income attributable to CME Ltd.	$ 40,643	$ (7,745)	$ 27,935	$ (11,065)		$ (19,627)	$ (141,317)	$ (40,435)	$ 49,768	$ (180,291)	$ (114,901)
Net (loss) / income per share:
Continuing operations — basic	$ 0.13	$ (0.03)	$ 0.09	$ (0.05)	$ 0.07	$ (0.09)	$ (0.96)	$ (0.27)	$ 0.17	$ (1.18)	$ (0.70)
Continuing operations — diluted	0.10	(0.03)	0.07	(0.05)	0.06	(0.09)	(0.96)	(0.27)	0.15	(1.18)	(0.70)
Discontinued operations — basic	0.02	(0.04)	0.01	(0.04)	0.00	(0.05)	(0.02)	(0.04)	(0.03)	(0.10)	(0.20)
Discontinued operations — diluted	0.01	(0.04)	0.00	(0.04)	0.00	(0.05)	(0.02)	(0.04)	(0.03)	(0.10)	(0.20)
Net (loss) / income attributable to CME Ltd. — basic	$ 0.15	$ (0.07)	$ 0.10	$ (0.09)	0.07	$ (0.14)	$ (0.98)	$ (0.31)	0.14	(1.28)	(0.90)
Net (loss) / income attributable to CME Ltd. — diluted					$ 0.06				$ 0.12	$ (1.28)	$ (0.90)