v3.20.1

Property, Plant and Equipment and Other Intangibles (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Property, Plant and Equipment [Line Items] |  |  |
Interest Costs Threshold For Capitalization Construction In Process | $ 500 |  |
Long-term Debt, Weighted Average Interest Rate, over Time | 4.60% | 4.80% | 4.80%
Property, Plant and Equipment, Gross | $ 8,431,227 | $ 7,628,592 |
Depreciation expense | $ 242,900 | 214,400 | $ 196,300
Finite-Lived Intangible Asset, Useful Life | 19 years |  |
Amortization of Intangible Assets | $ 3,300 | 1,600 | $ 400
Impairments |  | 49,100 |
Property, Plant and Equipment, Other Types [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | 284,674 | 261,075 |
Capitalized Interest [Member] | Property, Plant and Equipment, Other Types [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 86,400 | $ 67,600 |
Minimum [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Finite-Lived Intangible Asset, Useful Life | 7 years |  |
Maximum [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Finite-Lived Intangible Asset, Useful Life | 30 years |  |

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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 + Details
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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 + Details
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- Definition Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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