Debt - Additional Information (Detail) - USD ($)		9 Months Ended
Apr. 30, 2018	Sep. 30, 2020
Debt Instrument [Line Items]
Term of loan	5 years
Agreement date	Apr. 30, 2018
Senior secured revolving credit facility commitment	$ 750,000,000
Sub-facility for letter of credit	$ 60,000,000
Percentage of swing line sub facility	10.00%
Increase in aggregate principal amount	$ 250,000,000
Description of line of credit	The Company will be required to maintain a fixed charge coverage ratio of at least 1.00:1.00 as of the end of each fiscal quarter if excess availability under the Credit Facility falls below the greater of 12.5% of the borrowing base or $60 million.
Minimum amount of credit facility required to maintain coverage ratio percentage	12.50%
Minimum amount of credit facility required to maintain coverage ratio	$ 60,000,000
Fixed charge coverage ratio	100.00%
Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility borrowings		$ 0
Line of Credit Facility, Available Borrowing Capacity		$ 209,000,000
Line Of credit Unused Capacity Percentage		97.00%
Letters of credit		$ 7,000,000
Casualty insurance, expiration month and year		2021-07
Minimum [Member]
Debt Instrument [Line Items]
Unused portion of commitment fee range	0.25%
Maximum [Member]
Debt Instrument [Line Items]
Unused portion of commitment fee range	0.375%
Canadian Subsidiaries [Member]
Debt Instrument [Line Items]
Senior secured revolving credit facility commitment	$ 100,000,000
UK Subsidiaries [Member]
Debt Instrument [Line Items]
Senior secured revolving credit facility commitment	$ 40,000,000

Casualty insurance expiration month and year.

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- Definition

Line of credit facility covenant terms fixed charge coverage ratio.

+ References

No definition available.

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- Definition

Line of credit amount unused expressed as a percentage.

+ References

No definition available.

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- Definition

Minimum amount of credit facility required to maintain coverage ratio.

+ References

No definition available.

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- Definition

Minimum amount of credit facility required to maintain coverage ratio percentage.

+ References

No definition available.

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- Definition

Percentage of swing line sub facility.

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- Definition

Senior secured revolving credit facility commitment.

+ References

No definition available.

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- Definition

Sub facility for letters of credit.

+ References

No definition available.

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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.

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- 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.

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- Definition

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

+ References

No definition available.

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- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Name Accounting Standards Codification
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-SubTopic 210
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-Subparagraph (SX 210.7-03(16))
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- Definition

Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.

+ References

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- Definition

Amount of increase (decrease) of the credit facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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- Definition

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

+ References

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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

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- 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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