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Leases - Narrative (Details) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 USD ($) lease | Sep. 30, 2019 USD ($)
Lessee, Lease, Description [Line Items] |  |
Right-of-use asset impairment charge | $ | $ 1.4 | $ 1.4
U.K. |  |
Lessee, Lease, Description [Line Items] |  |
Number of operating leases impaired | lease | 2 |

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- Definition Number of Operating Leases Impaired + References No definition available. + Details
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Period Type: | duration

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
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Period Type: | duration

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- Definition Amount of loss from impairment of right-of-use asset from operating lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 25 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=77888369&loc=SL77918431-209957 + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | debit
Period Type: | duration

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- Details
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Period Type: |