Credit Facility - Term Loan Maturities (Details) - Term Loan $ in Millions	Oct. 31, 2017 USD ($)
Debt Instrument [Line Items]
Debt maturities, 2018	$ 20.0
Debt maturities, 2019	40.0
Debt maturities, 2020	60.0
Debt maturities, 2021	120.0
Debt maturities, 2022	560.0
Long-term Debt	$ 800.0
Principal repayment, 2018 (percent)	2.50%
Principal repayment, 2019 (percent)	5.00%
Principal repayment, 2020 (percent)	7.50%
Principal repayment, 2021 (percent)	15.00%
Principal repayment, 2022 (percent)	70.00%

Long-Term Debt, Maturities, Repayments Of Principal In Next Twelve Months, Percent

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Long-Term Debt, Maturities, Repayments Of Principal In Year Five, Percent

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Long-Term Debt, Maturities, Repayments Of Principal In Year Four, Percent

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Long-Term Debt, Maturities, Repayments Of Principal In Year Three, Percent

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Long-Term Debt, Maturities, Repayments Of Principal In Year Two, Percent

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
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-Name Accounting Standards Codification
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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-Section S99
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-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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