Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Name:	us-gaap_Assets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Restatement of Previously Issued Condensed Financial Statements (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Current assets:
Inventory	$ 8,851		$ 8,851		$ 9,837
Total current assets	47,898		47,898		27,418
Total assets	51,564		51,564		31,437
Accumulated deficit	(124,885)		(124,885)		(117,539)
Total stockholders' equity	30,983		30,983		10,884
Total liabilities and stockholders' equity	51,564		51,564		$ 31,437
Condensed statement of operations
Cost of sales	6,229	$ 3,133	11,127	$ 6,796
Gross profit	4,536	5,792	14,491	10,009
Loss from operations	(7,279)	(4,789)	(8,389)	(10,664)
Net loss and comprehensive loss	$ (7,369)	$ (5,187)	$ (8,646)	$ (11,273)
Net loss per common share, basic and diluted	$ (0.44)	$ (0.42)	$ (0.55)	$ (0.91)
Condensed statement of cash flows
Net loss			$ (8,646)	$ (11,273)
Inventory			940	$ (1,584)
As previously reported
Current assets:
Inventory	$ 9,621		9,621
Total current assets	48,668		48,668
Total assets	52,334		52,334
Accumulated deficit	(124,115)		(124,115)
Total stockholders' equity	31,753		31,753
Total liabilities and stockholders' equity	52,334		52,334
Condensed statement of operations
Cost of sales	5,459		10,357
Gross profit	5,306		15,261
Loss from operations	(6,509)		(7,619)
Net loss and comprehensive loss	$ (6,599)		$ (7,876)
Net loss per common share, basic and diluted	$ (0.40)		$ (0.50)
Condensed statement of cash flows
Net loss			$ (7,876)
Inventory			170
Adjustment
Current assets:
Inventory	$ (770)		(770)
Total current assets	(770)		(770)
Total assets	(770)		(770)
Accumulated deficit	(770)		(770)
Total stockholders' equity	(770)		(770)
Total liabilities and stockholders' equity	(770)		(770)
Condensed statement of operations
Cost of sales	770		770
Gross profit	(770)		(770)
Loss from operations	(770)		(770)
Net loss and comprehensive loss	$ (770)		$ (770)
Net loss per common share, basic and diluted	$ (0.04)		$ (0.05)
Condensed statement of cash flows
Net loss			$ (770)
Inventory			$ 770