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Guarantor and Non-Guarantor Financial Information - Debt (Details) - USD ($) $ in Millions | 1 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2015 | Mar. 31, 2018 | Mar. 19, 2015
Financial Information |  |  |
Percentage ownership of subsidiary | 100.00% |  |
Unsecured senior notes issued March 19, 2015 |  |  |
Financial Information |  |  |
Debt issued |  | $ 500.0 | $ 500.0
Issuer Subsidiary | Unsecured senior notes issued March 19, 2015 |  |  |
Financial Information |  |  |
Debt issued | $ 500.0 |  |

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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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