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.

No definition available.

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- Definition

The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

+ References

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-Publisher FASB
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-SubTopic 10
-Section 45
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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Revenue (Details) - USD ($)	3 Months Ended	9 Months Ended
Revenue (Details) - USD ($)	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Retained earnings (accumulated deficit)	$ (1,511,900,000)	$ (1,511,900,000)		$ (1,510,700,000)
Revenue	481,800,000	1,406,300,000
Increase in accounts receivable		48,300,000	$ 27,900,000
United States [Member]
Disaggregation of Revenue [Line Items]
Revenue	286,600,000	834,200,000
Iceland [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 195,200,000	$ 572,100,000
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] \| Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Retained earnings (accumulated deficit)				$ 0