The minimum amount of Domestic Liquidity must maintain in order to be in compliance with the debt covenant.

No definition available.

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- Definition

Pro forma leverage ratio.

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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-Topic 944
-SubTopic 210
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the credit facility first became available, in CCYY-MM-DD format.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Details

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Long-Term Debt - Additional Information (Detail)		3 Months Ended		9 Months Ended
Long-Term Debt - Additional Information (Detail)	Dec. 19, 2018 USD ($)	Jan. 31, 2019 USD ($)	Jan. 31, 2018	Jan. 31, 2019 USD ($)	Jan. 31, 2018	Apr. 30, 2018 USD ($)
Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility borrowings		$ 226,900,000		$ 226,900,000
Line of credit facility, remaining borrowing capacity		420,200,000		420,200,000
Previous Term Loan
Debt Instrument [Line Items]
Average interest rate			2.65%		2.49%
Standby Letters of Credit
Debt Instrument [Line Items]
Long-term debt arrangement		2,900,000		2,900,000		$ 2,900,000
Standby Letters of Credit \| Other Financial Institutions
Debt Instrument [Line Items]
Long-term debt arrangement		$ 10,400,000		$ 10,400,000		7,400,000
Previous Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility borrowings						0
Line of credit facility, remaining borrowing capacity						122,100,000
Credit Agreement
Debt Instrument [Line Items]
Credit agreement initiation date	Dec. 19, 2018
Line of credit facility borrowings	$ 226,900,000
Average interest rate		3.64%		3.42%
Unamortized debt issuance costs		$ 4,200,000		$ 4,200,000		2,700,000
Credit Agreement \| Maximum
Debt Instrument [Line Items]
Pro forma leverage ratio	3.25
Credit Agreement \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Applicable margin on variable interest rate				2.00%
Credit Agreement \| Maximum \| Base Rate Loans
Debt Instrument [Line Items]
Applicable margin on variable interest rate				1.00%
Credit Agreement \| Minimum
Debt Instrument [Line Items]
Pro forma domestic liquidity	$ 50,000,000
Credit Agreement \| Minimum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Applicable margin on variable interest rate				1.25%
Credit Agreement \| Minimum \| Base Rate Loans
Debt Instrument [Line Items]
Applicable margin on variable interest rate				0.25%
Credit Agreement \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument term	5 years
Line of credit facility, maximum borrowing capacity	$ 650,000,000
Line of credit facility, maturity date				Dec. 19, 2023
Long-term debt		$ 226,900,000		$ 226,900,000		$ 238,900,000
Credit Agreement \| Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Quarterly commitment fee on average daily unused amount of Credit Facilities				0.35%
Credit Agreement \| Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Quarterly commitment fee on average daily unused amount of Credit Facilities				0.20%