Principal Business Activity and Significant Accounting Policies - Receivables and Credit Policy (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Receivables and Credit Policy
Accounts receivable, gross	$ 59,378	$ 22,486
Less: Allowance for doubtful accounts	(95)	(343)
Non-current portion of receivables	(321)	(384)
Total accounts receivable, net	58,962	21,759
Trade receivables
Receivables and Credit Policy
Accounts receivable, gross	54,322	22,189
Notes receivable
Receivables and Credit Policy
Accounts receivable, gross	$ 5,056	$ 297

Accounts Receivable Noncurrent

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

For unclassified balance sheet, amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business.

+ References

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- Definition

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

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