Amortized Cost, Gross Unrealized Gains (Losses) and Fair Value of Available-For-Sale Securities (Detail) - USD ($) $ in Thousands	Jan. 31, 2019	Jan. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 336,292	$ 224,005
Unrealized Gains	532	293
Unrealized (Losses)	(300)	(485)
Fair Value	336,524	223,813
Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	279,426	165,337
Unrealized Gains	39	11
Unrealized (Losses)	(233)	(223)
Fair Value	279,232	165,125
Short-term Investments \| Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	227,287	111,612
Unrealized Gains	24
Unrealized (Losses)	(214)	(184)
Fair Value	227,097	111,428
Short-term Investments \| Municipal And Pre-Refunded Municipal Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	43,677	52,474
Unrealized Gains	15	11
Unrealized (Losses)	(18)	(39)
Fair Value	43,674	52,446
Short-term Investments \| Federal Government Agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,458
Fair Value	1,458
Short-term Investments \| Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,050	1,251
Fair Value	1,050	1,251
Short-term Investments \| Commercial Paper
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,979
Fair Value	2,979
Short-term Investments \| Treasury Bills
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,975
Unrealized (Losses)	(1)
Fair Value	2,974
Long Term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	56,866	58,668
Unrealized Gains	493	282
Unrealized (Losses)	(67)	(262)
Fair Value	57,292	58,688
Long Term Investments \| Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	34,265	39,853
Unrealized Gains	34
Unrealized (Losses)	(63)	(228)
Fair Value	34,236	39,625
Long Term Investments \| Municipal And Pre-Refunded Municipal Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,554	9,873
Unrealized Gains	7	8
Unrealized (Losses)	(3)	(24)
Fair Value	7,558	9,857
Long Term Investments \| Federal Government Agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	6,603
Unrealized Gains	2
Unrealized (Losses)	(1)
Fair Value	6,604
Long Term Investments \| Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,143	2,969
Fair Value	2,143	2,969
Long Term Investments \| Mutual Funds, Held in Rabbi Trust
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	6,301	5,973
Unrealized Gains	450	274
Unrealized (Losses)		(10)
Fair Value	$ 6,751	$ 6,237

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

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

- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesDebtSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FinancialInstrumentAxis=urbn_ShortTermMarketableInvestmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=urbn_MunicipalAndPreRefundedMunicipalBondsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=urbn_FederalGovernmentAgenciesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_CertificatesOfDepositMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_CommercialPaperMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_USTreasuryBillSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=urbn_LongTermMarketableInvestmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_MutualFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: