Number of shares of equity interests acquired by acquire entity.

No definition available.

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Namespace Prefix:	rba_
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Balance Type:	na
Period Type:	duration

- Definition

The amount of cash paid per share of common stock owned in a business combination.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of equity shares of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

No definition available.

+ Details

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- Definition

Number of shares issuable per share of common stock owned in a business combination.

+ References

No definition available.

+ Details

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- Definition

Percentage of remaining units ownership interest for which it entered into a put/call agreement with one of the minority unitholders.

+ References

No definition available.

+ Details

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- Definition

This element represents pre-acquisition related costs incurred to effect a business combination which costs have been expensed during the period.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to amortization incurred in connection with a business combination for which the initial accounting was incomplete.

+ References

No definition available.

+ Details

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

- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to deferred income tax liabilities acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

No definition available.

+ Details

Name:	rba_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentDeferredIncomeTaxLiabilities
Namespace Prefix:	rba_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to goodwill acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Equity award exchange ratio in a business combinations.

+ References

No definition available.

+ Details

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Namespace Prefix:	rba_
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Period Type:	duration

- Definition

Integration Milestones and Performance Targets Period

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of additional interests in business.

+ References

No definition available.

+ Details

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

- Definition

The agreed cash outflow associated with the acquisition of business under the term of the agreement.

+ References

No definition available.

+ Details

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

- Definition

Percentage of non controlling interest classified as equity.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
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-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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-SubTopic 10
-Section 25
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Balance Type:	debit
Period Type:	duration

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Balance Type:	credit
Period Type:	duration

- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 30
-Name Accounting Standards Codification
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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-Section 50
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-Subparagraph (h)(1)
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

+ Details

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 4A
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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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

Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

+ References

No definition available.

+ Details

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- Definition

Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

+ References

No definition available.

+ Details

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- Definition

In a business combination achieved in stages, this element represents the amount of net gain (loss) recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

+ References

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

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Subparagraph e
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-Topic 942
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
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- Details

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- Details

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Business Combinations (Narrative) (Details) $ / shares in Units, £ in Millions, $ in Millions							3 Months Ended			6 Months Ended	9 Months Ended
	Mar. 20, 2023 USD ($)	Jan. 22, 2023 USD ($) $ / shares shares	Jan. 03, 2023 USD ($) shares	May 04, 2022	Aug. 09, 2021 USD ($)	Aug. 09, 2021 GBP (£)	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)
Business Acquisition [Line Items]
Decrease to goodwill							$ 185.7
Amortization								$ (5.2)	$ (0.6)
Gain on remeasurements of investment upon acquisition											$ 1.4	$ 0.0
IAA
Business Acquisition [Line Items]
Total purchase price	$ 6,646.2
Cash consideration per share \| $ / shares		$ 12.80
Shares issued per share		0.5252
Cash consideration	$ 1,714.2	$ 1,700.0
Common stock consideration (in shares) \| shares		70,300,000
Assumption of net debt		$ 1,200.0
Equity award exchange ratio	0.763139
Increase to intangible assets							257.6
Increase to deferred income tax liabilities							62.4
Acquiree's revenue							557.4			$ 1,200.0
Acquiree's net income							$ 71.3			$ 148.2
Acquisition-related costs												232.6
Pre-acquisition transaction costs												$ 60.0
VeriTread
Business Acquisition [Line Items]
Total purchase price			$ 32.4
Cash consideration			$ 28.1
Number of shares acquired \| shares			1,056,338
Cash consideration for additional interest investment			$ 3.0
Voting equity interests owned including previous interest, percentage			75.00%
Prior holdings of issued and outstanding shares, percent			11.00%
Fair value of previously held interest			$ 4.3
Gain on remeasurements of investment upon acquisition			$ 1.4
Remaining units ownership interest, percentage			21.00%
Non-controlling interest classified as equity, percentage			4.00%
Integration milestones and performance targets period			3 years
VeriTread \| Existing stockholders
Business Acquisition [Line Items]
Cash consideration			$ 25.1
Number of shares acquired \| shares			8,889,766
Euro Auctions
Business Acquisition [Line Items]
Cash consideration under the terms of the SPA, to be paid on closing					$ 1,020.0	£ 775.0
2021 USD Notes
Business Acquisition [Line Items]
Redemption price percentage				100.00%
Senior Notes \| IAA
Business Acquisition [Line Items]
Assumption of net debt		$ 500.0
Redemption price percentage		102.75%