Debt Conversion, Hypothetical Share Price One, Per Share

No definition available.

Name:	uri_DebtConversionHypotheticalSharePriceOnePerShare
Namespace Prefix:	uri_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Covenant Terms, Maximum Revolving Credit Amount, Percentage

+ References

No definition available.

+ Details

Name:	uri_DebtInstrumentCovenantTermsMaximumRevolvingCreditAmountPercentage
Namespace Prefix:	uri_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Derivative, Convertible, Increase (Decrease) in Additional Paid in Capital

+ References

No definition available.

+ Details

Name:	uri_DerivativeConvertibleIncreaseDecreaseinAdditionalPaidinCapital
Namespace Prefix:	uri_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Derivative, Convertible Shares

+ References

No definition available.

+ Details

Name:	uri_DerivativeConvertibleShares
Namespace Prefix:	uri_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Derivative, Effective Conversion Price of Convertible Notes

+ References

No definition available.

+ Details

Name:	uri_DerivativeEffectiveConversionPriceofConvertibleNotes
Namespace Prefix:	uri_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Derivative, Effective Conversion Price of Convertible Notes, Premium Over Closing Price of Stock at Issuance, Percentage

+ References

No definition available.

+ Details

Name:	uri_DerivativeEffectiveConversionPriceofConvertibleNotesPremiumOverClosingPriceofStockatIssuancePercentage
Namespace Prefix:	uri_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(5))

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

+ Details

Name:	us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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

- Definition

The premium (cost) of a hedge, expensed during the period.

+ References

No definition available.

+ Details

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

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

Name:	us-gaap_SharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentAxis=uri_AblFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=uri_ConvertibleNotes4PercentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_ConvertibleDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Debt (Narrative) (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	1 Months Ended	3 Months Ended
	Nov. 30, 2009	Mar. 31, 2015	Nov. 10, 2009	Mar. 31, 2014
Convertible subordinated notes—4 percent
Debt Instrument
Hedge transactions cost	$ 26,000,000
Hedge transactions cost decrease in APIC	17,000,000
Convertible note hedge transactions shares (in shares)		0.7
Effective conversion price (in dollars per share)		$ 15.56
Percentage premium over price at issuance		75.00%
Closing price at issuance (in dollars per share)			$ 8.89
Market price per share (in dollars per share)		$ 90
ABL Facility
Debt Instrument
Maximum revolving credit amount percentage		10.00%
Convertible senior notes \| Convertible subordinated notes—4 percent
Debt Instrument
Face amount	$ 173,000,000	$ 8,000,000
Stated interest rate		4.00%		4.00%
Common stock \| Convertible subordinated notes—4 percent
Debt Instrument
Convertible equity shares (in shares)		0.6