EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income / (loss) from continuing operations		$ 56,025	$ 10,609	$ 23,675	$ 6,756	$ 40,710	$ (5,007)	$ 25,638	$ (10,278)	$ 97,065	$ 51,063	$ (179,679)
Net loss attributable to noncontrolling interests										(79)	(341)	(306)
Less: preferred share accretion paid in kind (Note 12)										(4,777)	(9,694)	(13,701)
Less: income allocated to Series B Preferred Shares										(29,956)	(16,994)	0
Income / (loss) from continuing operations available to common shareholders, net of noncontrolling interest										62,411	24,716	(193,074)
Income / (loss) from discontinued operations, net of tax (Note 3)		$ 0	$ 57,882	$ 2,350	$ 316	$ 126	$ (2,926)	$ 2,160	$ (996)	60,548	(1,636)	(918)
Net income / (loss) attributable to CME Ltd. available to common shareholders — basic										103,322	23,747	(193,992)
Dilutive effect of Series B Preferred Shares										3,653	3,829	0
Net income / (loss) attributable to CME Ltd. available to common shareholders — diluted										$ 106,975	$ 27,576	$ (193,992)
Weighted average outstanding shares of common stock — basic (1)	[1]									230,562,000	155,846,000	151,017,000
Dilutive effect of common stock warrants, employee stock options and RSUs										27,132,000	80,558,000	0
Weighted average outstanding shares of common stock — diluted										257,694,000	236,404,000	151,017,000
Net loss per share:
Continuing operations — basic		$ 0.15	$ 0.03	$ 0.06	$ 0.02	$ 0.14	$ (0.05)	$ 0.09	$ (0.08)	$ 0.27	$ 0.16	$ (1.28)
Continuing operations — diluted		0.15	0.03	0.06	0.01	0.11	(0.05)	0.07	(0.08)	0.25	0.12	(1.28)
Discontinued operations — basic		0.00	0.15	0.01	0.00	0.00	(0.02)	0.01	(0.01)	0.18	(0.01)	0.00
Discontinued operations — diluted		0.00	0.15	0.00	0.00	0.00	(0.02)	0.00	(0.01)	0.17	0.00	0.00
Attributable to CME Ltd. — basic		0.15	0.18	0.07	0.02	0.14	(0.07)	0.10	(0.09)	0.45	0.15	(1.28)
Attributable to CME Ltd. — diluted		$ 0.15	$ 0.18	$ 0.06	$ 0.01	$ 0.11	$ (0.07)	$ 0.07	$ (0.09)	$ 0.42	$ 0.12	$ (1.28)
Common Class A [Member] | T W Investor [Member]
Incremental Common Shares Attributable to Dilutive Effect of Conversion of Preferred Stock										11,211,449	11,211,449	11,211,449
Discontinued Operations, Held-for-sale [Member]
Less: income allocated to Series B Preferred Shares										$ (19,637)	$ 667	$ 0

[1] For the purpose of computing basic earnings per share, the 11,211,449 shares of Class A common stock underlying the Series A Preferred Share are included in the weighted average outstanding shares of common stock - basic, because the rights of the Series A Preferred Share are considered substantially similar to that of our Class A common stock.