Revenue From Contracts with Customers - Current and Deferred Contracts (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Movement in Deferred Revenue [Roll Forward]
Balance as of December 31, 2017	$ 20,784
Revenue recognized that was included in the deferred revenue balance at the beginning of the period	(16,556)
Balance as of March 31, 2018	4,228
Balance as of December 31, 2017	0
Increases due to cash received, excluding amounts recognized as revenue during the period	8,242
Balance as of March 31, 2018	$ 8,242

Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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- Definition

The noncurrent portion of deferred revenue amount as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Amount of revenue recognized that was previously reported as deferred or unearned revenue.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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