Cover Document - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 12, 2018	Jun. 30, 2017
Entity Registrant Name	Groupon, Inc.
Entity Central Index Key	0001490281
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY
Amendment Flag	false
Common Stock, Shares, Outstanding		561,532,375
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 1,597,986,820