Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ 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(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
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

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
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

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 http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=ibp_TermLoanAgreementMember
Namespace Prefix:
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Balance Type:
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- Details

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Name:	us-gaap_DebtInstrumentAxis=ibp_AblCreditAgreementMember
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- Details

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Period Type:

- Details

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- Details

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Period Type:

- Details

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Long-term Debt - Additional Information (Detail) - USD ($)			9 Months Ended
	Jun. 19, 2018	Apr. 13, 2017	Sep. 30, 2018	Sep. 30, 2017	Nov. 30, 2017
Debt Instrument [Line Items]
Debt instrument, wrote off fees			$ 1,164,000	$ 1,201,000
Term Loan Agreement [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 300,000,000
Term loan facility maturity period		7 years
ABL Credit Agreement [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity		$ 100,000,000
ABL Credit Agreement [Member] \| Letter of Credit [Member]
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity		$ 50,000,000
Term Loan Second Amendment [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 397,800,000
Debt instrument, extended maturity date range, start	Apr. 15, 2024
Debt instrument, extended maturity date range, end	Apr. 15, 2025
Debt instrument, wrote off fees	$ 1,100,000
Amended Term Loan Agreement [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, face amount					$ 297,800,000
ABL Third Amendment [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity	$ 150,000,000
Debt instrument, extended maturity date range, start	Apr. 13, 2022
Debt instrument, extended maturity date range, end	Jun. 19, 2023