XML 43 R33.htm IDEA: XBRL DOCUMENT
v3.21.2

REVENUE - Deferred Revenue Rollforward (Details) - USD ($) $ in Thousands | 6 Months Ended
--- | ---
Jun. 30, 2021 | Jun. 30, 2020
Revenue from Contract with Customer, Liability [Roll Forward] |  |
Beginning balance | $ 54,792 | $ 26,307
Amount from beginning balance recognized into revenue | (41,498) | (19,833)
Recognition of deferred revenue | (45,378) | (30,737)
Deferral of revenue | 103,081 | 68,897
Ending balance | $ 70,997 | $ 44,634

X
- Definition Contract With Customer, Liability, Additions During the Period + References No definition available. + Details
Name: | duol_ContractWithCustomerLiabilityAdditionsDuringThePeriod
Namespace Prefix: | duol_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Contract with Customer, Liability, Revenue Recognized, Excluding Opening Balance + References No definition available. + Details
Name: | duol_ContractWithCustomerLiabilityRevenueRecognizedExcludingOpeningBalance
Namespace Prefix: | duol_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Revenue from Contract with Customer, Liability + References No definition available. + Details
Name: | duol_RevenueFromContractWithCustomerLiabilityRollForward
Namespace Prefix: | duol_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=123360276&loc=SL49130531-203044 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123360276&loc=SL49130532-203044 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130549-203045 + Details
Name: | us-gaap_ContractWithCustomerLiabilityCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130549-203045 + Details
Name: | us-gaap_ContractWithCustomerLiabilityRevenueRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration