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Senior Debt (Details) - Unsecured Debt | Jun. 30, 2018 USD ($)
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Revolver |
Long-term debt |
Maximum borrowing capacity | $ 1,450,000,000.00
Maximum borrowing capacity, additional amount | 350,000,000.0
Term Loan |
Long-term debt |
Principal amount at maturity | 385,000,000.0
Maximum borrowing capacity, additional amount | $ 65,000,000.0

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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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