For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of revenue recognized arising from contract liability from change in timeframe for performance obligation to be satisfied.

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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 revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Revenue from Contracts with Customers Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue, Major Customer [Line Items]
Amounts included in deferred revenue for performance obligations satisfied or partially satisfied	$ 900,000		$ 1,600,000
Major Customer
Revenue, Major Customer [Line Items]
Revenues	$ 23,000,000	$ 0	$ 45,100,000	$ 0
Major Customer \| Customer Concentration Risk \| Sales Revenue, Net
Revenue, Major Customer [Line Items]
Concentration risk, percentage	10.40%		10.40%