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v3.10.0.1

Subsequent Events (Details) |  | 6 Months Ended |
--- | --- | --- | ---
Jul. 13, 2018 USD ($) | Jun. 30, 2018 USD ($) | Jun. 30, 2017 USD ($) | Jul. 13, 2018 GBP (£)
Subsequent Event [Line Items] |  |  |  |
Repayments of long-term debt |  | $ 540,000,000 | $ 285,000,000 |
Unsecured Debt | Term Loan |  |  |  |
Subsequent Event [Line Items] |  |  |  |
Principal amount at maturity |  | 385,000,000.0 |  |
Maximum borrowing capacity, additional amount |  | $ 65,000,000.0 |  |
Unsecured Debt | Term Loan | Subsequent Event |  |  |  |
Subsequent Event [Line Items] |  |  |  |
Principal amount at maturity | $ 385,000,000 |  |  | £ 290,000,000
Repayments of long-term debt | 1,500,000 |  |  |
Maximum borrowing capacity, additional amount | $ 65,000,000.0 |  |  | £ 50,000,000.0

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
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