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Other Comprehensive Income (Loss): Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start | $ (30,655) | $ (26,916)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End | (26,922) | (25,695)
Accumulated Defined Benefit Plans Adjustment |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start | (15,077) | (9,937)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax | 55 | 0
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End | (13,717) | (9,655)
Accumulated Defined Benefit Plans Adjustment | Reclassification out of Accumulated Other Comprehensive Income |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 1,305 | 282
Accumulated Other Comprehensive Income (loss) |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax | 236 | (334)
Accumulated Other Comprehensive Income (loss) | Reclassification out of Accumulated Other Comprehensive Income |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 3,497 | 1,555
Interest Rate Swaps | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start | (15,122) | (17,307)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax | 0 | 0
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End | (13,492) | (15,668)
Interest Rate Swaps | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent | Reclassification out of Accumulated Other Comprehensive Income |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 1,630 | 1,639
Commodity Contracts | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start | (456) | 328
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax | 181 | (334)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End | 287 | (372)
Commodity Contracts | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent | Reclassification out of Accumulated Other Comprehensive Income |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | $ 562 | $ (366)

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- Definition Accumulated Other Comprehensive Income [Roll Forward] + References No definition available. + Details
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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(30)(a)(4)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(a)(3)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669686-108580 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(2)(ii) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e681-108580 + Details
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- Definition Amount after tax, before reclassification adjustments of other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118261656&loc=d3e32136-110900 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450520&loc=d3e32583-110901 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669686-108580 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 55 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=121640130&loc=d3e1436-108581 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 20 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900 + Details
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