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Debt - Schedule of Contractual Interest Expense and Amortization of Discount on Notes (Detail) $ in Millions | 6 Months Ended
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Dec. 31, 2017 USD ($)
Debt Instrument [Line Items] |
Amortization of discount and debt issuance costs | $ 8.4
Purchase Agreement [Member] | 0.50% Convertible Senior Notes due 2022 [Member] | Wells Fargo Securities, LLC [Member] |
Debt Instrument [Line Items] |
Interest expense | 1.3
Amortization of discount and debt issuance costs | 8.4
Total interest | $ 9.7

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- Definition Amount of amortization expense attributable to debt discount (premium) and debt issuance costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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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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- Definition Amount of the cost of borrowed funds accounted for as interest expense for debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Definition Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph 8 -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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