XML 52 R41.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Inventories (Narrative) (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Inventories [Abstract] |  |
Inventory amount, FIFO | $ 59,021 | $ 54,837
Inventory amount, weighted average cost | $ 19,607 | $ 18,634

X
- Definition The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different valuation methods. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766 + Details
Name: | us-gaap_FIFOInventoryAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_InventoryDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of weighted average cost inventory present at the reporting date when inventory is valued using different valuation methods. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766 + Details
Name: | us-gaap_WeightedAverageCostInventoryAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant