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Intangible Assets - Narrative (Details) - USD ($) | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019 | Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract] |  |  |  |  |  |
Amortization expense | $ 5,300,000 | $ 6,200,000 | $ 10,600,000 | $ 12,400,000 |  |
Goodwill [Line Items] |  |  |  |  |  |
Goodwill | 1,432,787,000 | $ 1,432,787,000 | 1,432,787,000 | $ 1,432,787,000 | $ 1,432,787,000 | $ 1,432,787,000
Non-Strategic |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Gross goodwill | 200,000,000.0 |  | 200,000,000.0 |  | 200,000,000 |
Accumulated impairments | 114,100,000 |  | 114,100,000 |  | 114,100,000 |
Accumulated divestiture related write-offs | 85,900,000 |  | 85,900,000 |  | 85,900,000 |
Goodwill | $ 0 |  | $ 0 |  | $ 0 |

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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266 + Details
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- Definition Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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