Debt - New Revolving Credit Agreement (Details) - Revolving Credit Facility - New Revolving Credit Agreement $ in Millions	Jan. 31, 2018 USD ($)
Debt Instrument [Line Items]
Debt instrument leverage ratio springing financial maintenance covenant	4.75
Maximum
Debt Instrument [Line Items]
Debt instrument reimbursed amount	$ 54

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.

No definition available.

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