Subsequent events (Details) - Subsequent Event	Jul. 11, 2022 $ / shares shares
Subsequent Event [Line Items]
Shares outstanding exchange options (in shares)	7,373,532
Stock Appreciation Rights
Subsequent Event [Line Items]
Shares outstanding exchange non options (in shares)	22,655
Stock Options And SARs
Subsequent Event [Line Items]
Exercise price range options and non options (in dollars per share) \| $ / shares	$ 11.13
Restricted Stock Units (RSUs)
Subsequent Event [Line Items]
Conversion basis	1

Share-Based Payment Arrangement Conversion Basis

No definition available.

Name:	udmy_ShareBasedPaymentArrangementConversionBasis
Namespace Prefix:	udmy_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Share-Based Payment Arrangement, Non-Option Equity Instruments, Exercise Price Range, Shares Outstanding

+ References

No definition available.

+ Details

Name:	udmy_ShareBasedPaymentArrangementNonOptionEquityInstrumentsExercisePriceRangeSharesOutstanding
Namespace Prefix:	udmy_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Share-based Payment Arrangement, Option and Non-Option Equity Instruments, Exercise Price Range, Outstanding, Weighted Average Exercise Price

+ References

No definition available.

+ Details

Name:	udmy_ShareBasedPaymentArrangementOptionAndNonOptionEquityInstrumentsExercisePriceRangeOutstandingWeightedAverageExercisePrice
Namespace Prefix:	udmy_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_StockAppreciationRightsSARSMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=udmy_ShareBasedPaymentArrangementOptionAndStockAppreciationRightsSARsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: