Restatement of Previously Issued Consolidated Financial Statements - Consolidated Statements of Cash Flows Impact (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net cash used in operating activities	$ 8,097	$ 13,910	$ 1,322	$ 24,511	$ (13,542)	$ 24,313	$ (7,695)	$ 32,282	$ (22,815)	$ (15,094)
Net cash used in investing activities	(1,896)	(1,099)	(2,424)	489	(3,611)	(1,065)	(5,165)	(1,651)	(43,805)	(52,322)
Net cash provided by financing activities	(8,151)	(19,761)	(1,190)	(33,010)	14,861	(30,083)	10,568	(36,784)	68,504	67,671
Increase in cash	(1,950)	(6,950)	(2,292)	(8,010)	(2,292)	(6,835)	(2,292)	(6,153)	1,884	255
Cash at beginning of the year	2,292	8,445	2,292	8,445	2,292	8,445	$ 2,292	8,445	6,561	6,306
Cash at end of the year	$ 342	1,495	$ 0	435	$ 0	1,610		2,292	8,445	6,561
Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net cash used in operating activities		9,995							(23,049)	(15,685)
Net cash used in investing activities		(214)							(43,570)	(51,713)
Net cash provided by financing activities		(16,731)							68,503	67,653
Increase in cash									1,884	255
Cash at beginning of the year		8,445		$ 8,445		$ 8,445		$ 8,445	6,561	6,306
Cash at end of the year		$ 1,495							$ 8,445	$ 6,561

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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