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Operating Leases - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Operating Leased Assets [Line Items] |  |  |
Total rent expense under all operating leases | $ 48.2 | $ 51.8 | $ 53.8
U.S. |  |  |
Operating Leased Assets [Line Items] |  |  |
Total term of lease facility | 30 years |  |
Initial term of lease facilities | 15 years |  |
Number of additional extensions on lease facility | 3 |  |
Extended period of lease under option | 5 years |  |
U.K. |  |  |
Operating Leased Assets [Line Items] |  |  |
Total term of lease facility | 20 years |  |
Brazil |  |  |
Operating Leased Assets [Line Items] |  |  |
Total term of lease facility | 5 years |  |

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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
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