Percentage of fixed interest rate of equipment financing facilities.

No definition available.

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Namespace Prefix:	becn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: 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(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	instant

- 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

The effective interest rate at the end of the reporting period.

+ 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 210.5-02.19(b),22(b))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	instant

- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=becn_TermLoanDueMayNineteenTwoThousandAndTwentyEightMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=becn_SeniorNotesDueInNovemberTwoThousandTwentySixMember
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- Details

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- Details

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- Details

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- Details

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- Details

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Financing Arrangements - Long-term Debt Instruments - Footnotes (Detail)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2022	Dec. 31, 2021	May 10, 2021	Oct. 28, 2019	Oct. 09, 2019
Equipment Financing Facilities \| Minimum
Debt Instrument [Line Items]
Equipment financing facilities, fixed interest rate percentage	2.33%
Equipment Financing Facilities \| Maximum
Debt Instrument [Line Items]
Equipment financing facilities, fixed interest rate percentage	2.89%
2028 Term Loan
Debt Instrument [Line Items]
Debt interest rate at period end	2.59%	3.31%	2.34%
2026 Senior Notes
Debt Instrument [Line Items]
Debt interest rate at period end		4.50%			6.375%	4.50%
2029 Senior Notes
Debt Instrument [Line Items]
Debt interest rate at period end		4.125%		4.125%
Revolving Lines of Credit \| 2026 Revolver \| U.S.
Debt Instrument [Line Items]
Line of credit facility, interest rate at period end		2.48%
Term Loan \| 2026 Revolver \| Canada
Debt Instrument [Line Items]
Debt interest rate at period end		3.95%