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Property, Plant and Equipment - Components of Property, Plant and Equipment (Detail) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019
Property Plant And Equipment [Line Items] |  |
Total property, plant and equipment, at cost | $ 4,114.8 | $ 3,905.0
Accumulated depreciation | (1,011.5) | (894.9)
Property, plant and equipment, net | 3,103.3 | 3,010.1
Logistics Facilities and Railcars |  |
Property Plant And Equipment [Line Items] |  |
Total property, plant and equipment, at cost | $ 385.9 | 385.5
Logistics Facilities and Railcars | Minimum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 20 years |
Logistics Facilities and Railcars | Maximum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 25 years |
Storage Facilities |  |
Property Plant And Equipment [Line Items] |  |
Total property, plant and equipment, at cost | $ 19.5 | 19.5
Storage Facilities | Minimum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 20 years |
Storage Facilities | Maximum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 25 years |
Other |  |
Property Plant And Equipment [Line Items] |  |
Total property, plant and equipment, at cost | $ 20.9 | 13.0
Other | Minimum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 20 years |
Other | Maximum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 25 years |
Construction-In-Progress |  |
Property Plant And Equipment [Line Items] |  |
Total property, plant and equipment, at cost | $ 208.7 | 149.3
Gathering Assets | Pipelines |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 22 years |
Total property, plant and equipment, at cost | $ 1,449.7 | 1,352.7
Gathering Assets | Compressors, Pumping Stations and Terminals |  |
Property Plant And Equipment [Line Items] |  |
Total property, plant and equipment, at cost | $ 770.8 | 725.9
Gathering Assets | Compressors, Pumping Stations and Terminals | Minimum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 22 years |
Gathering Assets | Compressors, Pumping Stations and Terminals | Maximum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 25 years |
Gas Plant Assets | Pipelines, Pipes and Valves |  |
Property Plant And Equipment [Line Items] |  |
Total property, plant and equipment, at cost | $ 460.0 | 460.0
Gas Plant Assets | Pipelines, Pipes and Valves | Minimum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 22 years |
Gas Plant Assets | Pipelines, Pipes and Valves | Maximum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 25 years |
Gas Plant Assets | Equipment |  |
Property Plant And Equipment [Line Items] |  |
Total property, plant and equipment, at cost | $ 428.3 | 428.2
Gas Plant Assets | Equipment | Minimum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 12 years |
Gas Plant Assets | Equipment | Maximum |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 30 years |
Gas Plant Assets | Buildings |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 35 years |
Total property, plant and equipment, at cost | $ 182.3 | 182.3
Gas Plant Assets | Processing and Fractionation Facilities |  |
Property Plant And Equipment [Line Items] |  |
Property, plant and equipment, Estimated useful life | 25 years |
Total property, plant and equipment, at cost | $ 188.7 | $ 188.6

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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=120391452&loc=d3e13212-122682 + Details
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