Supplemental Guarantors Consolidating Condensed Financial Information - Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Condensed Financial Statements, Captions
REVENUE	$ 12,324	$ 23,700	$ 31,813	$ 44,295
EXPENSES:
Depreciation and amortization	8,081	21,969	18,392	44,232
Impairment of goodwill	4,496	0	4,496	0
Cost of sales	88	33	105	43
Selling, general and administrative	4,807	5,005	10,514	10,651
Total operating expenses	17,472	27,007	33,507	54,926
LOSS FROM OPERATIONS	(5,148)	(3,307)	(1,694)	(10,631)
Interest income (expense), net	(6,032)	(6,187)	(12,086)	(12,397)
Foreign currency exchange gains (losses)	470	(34)	1,112	(85)
Other income	63	96	72	96
Loss before income taxes	(10,647)	(9,432)	(12,596)	(23,017)
Provision (benefit) for income taxes	(836)	204	(882)	(2)
Equity in loss of subsidiaries	0	0	0	0
NET LOSS	(9,811)	(9,636)	(11,714)	(23,015)
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions
REVENUE	(339)	(601)	(926)	(942)
EXPENSES:
Depreciation and amortization	0	(12)	0	(25)
Impairment of goodwill	0		0
Cost of sales	(19)	(276)	(283)	(290)
Selling, general and administrative	(320)	(325)	(643)	(652)
Total operating expenses	(339)	(613)	(926)	(967)
LOSS FROM OPERATIONS	0	12	0	25
Interest income (expense), net	0	0	0	0
Foreign currency exchange gains (losses)	0	0	0	0
Other income	0	0	0	0
Loss before income taxes	0	12	0	25
Provision (benefit) for income taxes	0	0	0	0
Equity in loss of subsidiaries	5,633	3,386	1,510	10,893
NET LOSS	5,633	3,398	1,510	10,918
Parent [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements, Captions
REVENUE	0	0	0	0
EXPENSES:
Depreciation and amortization	0	0	0	0
Impairment of goodwill	0		0
Cost of sales	0	0	0	0
Selling, general and administrative	130	137	260	260
Total operating expenses	130	137	260	260
LOSS FROM OPERATIONS	(130)	(137)	(260)	(260)
Interest income (expense), net	(6,407)	(6,039)	(12,618)	(11,913)
Foreign currency exchange gains (losses)	0	0	0	0
Other income	0	0	0	0
Loss before income taxes	(6,537)	(6,176)	(12,878)	(12,173)
Provision (benefit) for income taxes	0	0	0	0
Equity in loss of subsidiaries	(3,274)	(3,460)	1,164	(10,842)
NET LOSS	(9,811)	(9,636)	(11,714)	(23,015)
Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements, Captions
REVENUE	11,634	19,291	28,489	33,093
EXPENSES:
Depreciation and amortization	6,291	18,366	13,463	34,482
Impairment of goodwill	2,518		2,518
Cost of sales	52	317	332	327
Selling, general and administrative	3,984	4,010	8,653	8,637
Total operating expenses	12,845	22,693	24,966	43,446
LOSS FROM OPERATIONS	(1,211)	(3,402)	3,523	(10,353)
Interest income (expense), net	261	(145)	313	(466)
Foreign currency exchange gains (losses)	0	2	(1)	2
Other income	41	0	50	0
Loss before income taxes	(909)	(3,545)	3,885	(10,817)
Provision (benefit) for income taxes	6	1	47	(1)
Equity in loss of subsidiaries	(2,359)	74	(2,674)	(51)
NET LOSS	(3,274)	(3,472)	1,164	(10,867)
Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements, Captions
REVENUE	1,029	5,010	4,250	12,144
EXPENSES:
Depreciation and amortization	1,790	3,615	4,929	9,775
Impairment of goodwill	1,978		1,978
Cost of sales	55	(8)	56	6
Selling, general and administrative	1,013	1,183	2,244	2,406
Total operating expenses	4,836	4,790	9,207	12,187
LOSS FROM OPERATIONS	(3,807)	220	(4,957)	(43)
Interest income (expense), net	114	(3)	219	(18)
Foreign currency exchange gains (losses)	470	(36)	1,113	(87)
Other income	22	96	22	96
Loss before income taxes	(3,201)	277	(3,603)	(52)
Provision (benefit) for income taxes	(842)	203	(929)	(1)
Equity in loss of subsidiaries	0	0	0	0
NET LOSS	$ (2,359)	$ 74	$ (2,674)	$ (51)