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Leases Adoption of ASC 842 (Details) - USD ($) $ in Millions | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2019 | Jan. 01, 2019 | Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Total lease liabilities | $ 76.6 |  |
Operating lease right-of-use assets | $ 74.5 |  | $ 0.0
Accounting Standards Update 2016-02 [Member] |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Total lease liabilities |  | $ 73.1 |
Operating lease right-of-use assets |  | $ 71.0 |
Maximum [Member] |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Operating leases, term of contracts | 12 months |  |
Operating leases, option to extend | 5 years |  |

X
- Definition Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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X
- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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X
- Definition Lessee, Operating Lease, Term of Renewal Contract + References No definition available. + Details
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