Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e9038-108599

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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

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Business segments - Geography, Segment Reporting (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 433,847	$ 400,645	$ 388,802	$ 365,786	$ 339,836	$ 333,650	$ 326,754	$ 318,854	$ 1,589,080	$ 1,319,094	$ 1,949,857
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									938,333	808,912	1,373,714
Long-lived assets	370,029				395,107				370,029	395,107	408,722
Iceland [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									650,747	510,182	576,143
Long-lived assets	582,981				625,897				582,981	625,897	801,268
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 74,957				$ 78,701				$ 74,957	$ 78,701	$ 94,421