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Revenue From Contracts with Customers - Disaggregate Revenue (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
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Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Revenue, Initial Application Period Cumulative Effect Transition |  |  |  |
Total Revenues | $ 480,390 | $ 456,332 | $ 955,384 | $ 908,231
By-products and other |  |  |  |
Revenue, Initial Application Period Cumulative Effect Transition |  |  |  |
Total Revenues | 26,536 | 44,322 | 58,194 | 80,310
Graphite Electrodes - Three-to-five-year take-or-pay contracts |  |  |  |
Revenue, Initial Application Period Cumulative Effect Transition |  |  |  |
Total Revenues | 377,605 | 345,246 | 773,645 | 617,447
Graphite Electrodes - Short-term agreements and spot sales |  |  |  |
Revenue, Initial Application Period Cumulative Effect Transition |  |  |  |
Total Revenues | $ 76,249 | $ 66,764 | $ 123,545 | $ 210,474

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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045 + Details
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