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Fair Value of Assets & Liabilities - Narrative (Details) - USD ($) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019
Segment Reporting Information [Line Items] |  |
Fair value, asset (liability), unrealized gain (loss), OCI | $ 0 | $ 0
Corporate |  |
Segment Reporting Information [Line Items] |  |
Fixed asset impairments | 4,800,000 |
Disposition of Acquired Properties | Corporate |  |
Segment Reporting Information [Line Items] |  |
Asset impairment charges |  | 4,600,000
Reversed asset impairment charges |  | 700,000
Disposition of Acquired Properties | 2019 Business Optimization | Corporate |  |
Segment Reporting Information [Line Items] |  |
Asset impairment charges | $ 4,200,000 | 1,500,000
Leased Assets | 2019 Business Optimization | Corporate |  |
Segment Reporting Information [Line Items] |  |
Asset impairment charges |  | 14,000,000.0
Reversed asset impairment charges |  | 1,400,000
Leased Assets | Rebranding Initiative | Corporate |  |
Segment Reporting Information [Line Items] |  |
Asset impairment charges |  | $ 7,100,000

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- Definition Amount of unrealized gain (loss) recognized in other comprehensive income (OCI) from asset (liability) measured at fair value on recurring basis using unobservable input (level 3) and still held. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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