CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - 6 months ended Jun. 30, 2018 - USD ($) $ in Thousands	Total	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income [Member]	Noncontrolling Interest [Member]	Preferred Class A [Member] Series A Convertible Preferred Stock [Member]	Common Class A [Member] Common Stock [Member]	Common Class B [Member]	Common Class B [Member] Common Stock [Member]	Warrant [Member] Common Stock [Member]
BALANCE at Dec. 31, 2017	$ (5,770)	$ 1,905,779	$ (1,735,768)	$ (187,438)	$ 18	$ 0	$ 11,639		$ 0
BALANCE (in shares) at Dec. 31, 2017						1
BALANCE (in shares) at Dec. 31, 2017							145,486,497	0	0
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Stock-based compensation	2,240	2,240
Number of warrants exercised (in shares)										105,652,401
Stock and Warrants Issued During Period, Value, Preferred Stock and Warrants										$ 8,452
Exercise of warrants (Note 14)	105,652	97,200
Shares issuance, stock-based compensation (in shares)							982,109
Share issuance, stock-based compensation	0	(79)					$ 79
Adjustments Related to Tax Withholding for Share-based Compensation	753	753
Preferred dividend paid in kind	(4,777)	(4,777)
Net income / (loss)	33,097		33,291		(194)
Unrealized (loss) / gain on derivative instruments (Note 12)	(2,928)			(2,928)
Currency translation adjustment	(22,844)			(23,068)	224
Currency translation adjustment	(22,844)
BALANCE at Jun. 30, 2018	$ 103,917	$ 1,999,610	$ (1,702,477)	$ (213,434)	$ 48	$ 0	$ 20,170		$ 0
BALANCE (in shares) at Jun. 30, 2018						1
BALANCE (in shares) at Jun. 30, 2018							252,121,007	0	0