Income (Loss) Per Share Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income (Loss) from Continuing Operations, Per Basic Share	[1]	$ (0.01)	$ (0.09)	$ (0.06)	$ (0.17)
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	[1]	(0.01)	(0.01)	0.00	(0.01)
Earnings Per Share, Basic	[1]	$ (0.02)	$ (0.10)	$ (0.06)	$ (0.18)
Basic net income (loss) per share
Allocation of net loss - continuing operations		$ (5,403)	$ (48,768)	$ (26,272)	$ (92,307)
Less: Allocation of net income attributable to noncontrolling interests		2,547	3,173	6,579	6,696
Net loss from discontinued operations		(1,376)	(2,963)	(889)	(5,020)
Net loss attributable to Groupon, Inc.		$ (9,326)	$ (54,904)	$ (33,740)	$ (104,023)
Basic, weighted average number of shares outstanding	[1]	559,762,180	576,903,004	560,978,712	579,827,341
Diluted net income (loss) per share
Basic, weighted average number of shares outstanding	[1]	559,762,180	576,903,004	560,978,712	579,827,341
Diluted, weighted average number of shares outstanding	[1]	559,762,180	576,903,004	560,978,712	579,827,341
Common Class A [Member]
Income (Loss) from Continuing Operations, Per Basic Share	[2]	$ (0.01)		$ (0.06)
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	[2]	(0.01)		0.00
Earnings Per Share, Basic	[2]	$ (0.02)		$ (0.06)
Income (Loss) from Continuing Operations, Per Basic and Diluted Share	[3]		$ (0.09)		$ (0.17)
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic and Diluted Share	[3]		(0.01)		(0.01)
Earnings Per Share, Basic and Diluted	[3]		$ (0.10)		$ (0.18)
Basic net income (loss) per share
Allocation of net loss - continuing operations		$ (5,403)	$ (48,565)	$ (26,272)	$ (91,923)
Less: Allocation of net income attributable to noncontrolling interests		2,547	3,160	6,579	6,668
Allocation of net loss attributable to common stockholders - continuing operations		(7,950)	(51,725)	(32,851)	(98,591)
Net loss from discontinued operations		(1,376)	(2,951)	(889)	(4,999)
Net loss attributable to Groupon, Inc.		$ (9,326)	$ (54,676)	$ (33,740)	$ (103,590)
Basic, weighted average number of shares outstanding		559,762,180	574,503,028	560,978,712	577,427,365
Diluted net income (loss) per share
Basic, weighted average number of shares outstanding		559,762,180	574,503,028	560,978,712	577,427,365
Common Class B [Member]
Income (Loss) from Continuing Operations, Per Basic and Diluted Share	[3]		$ (0.09)		$ (0.17)
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic and Diluted Share	[3]		(0.01)		(0.01)
Earnings Per Share, Basic and Diluted	[3]		$ (0.10)		$ (0.18)
Basic net income (loss) per share
Allocation of net loss - continuing operations			$ (203)		$ (384)
Less: Allocation of net income attributable to noncontrolling interests			13		28
Allocation of net loss attributable to common stockholders - continuing operations			(216)		(412)
Net loss from discontinued operations			(12)		(21)
Net loss attributable to Groupon, Inc.			$ (228)		$ (433)
Basic, weighted average number of shares outstanding			2,399,976		2,399,976
Diluted net income (loss) per share
Basic, weighted average number of shares outstanding			2,399,976		2,399,976

[1] (1)The structure of the Company's common stock changed during the year ended December 31, 2016. Refer to Note 8, Stockholders' Equity and Compensation Arrangements, and Note 12, Income (Loss) per Share, for additional information.

[2] Three Months Ended June 30, 2017 Six Months Ended June 30, 2017Basic and diluted net income (loss) per share: Numerator Net income (loss) - continuing operations $(5,403) $(26,272)Less: Net income (loss) attributable to noncontrolling interests 2,547 6,579Net income (loss) attributable to common stockholders - continuing operations $(7,950) $(32,851)Net income (loss) attributable to common stockholders - discontinued operations (1,376) (889)Net income (loss) attributable to common stockholders $(9,326) $(33,740)Denominator Weighted-average common shares outstanding 559,762,180 560,978,712Basic and diluted net income (loss) per share (1): Continuing operations $(0.01) $(0.06)Discontinued operations (0.01) —Basic and diluted net income (loss) per share $(0.02) $(0.06)(1)The potentially dilutive impacts of outstanding equity awards, warrants and convertible senior notes have been excluded from the calculation of dilutive net income (loss) per share for the three and six months ended June 30, 2017 as their effect on net income (loss) per share from continuing operations was antidilutive.

[3] (1)The potentially dilutive impacts of a conversion of Class B to Class A shares, outstanding equity awards, warrants and convertible senior notes have been excluded from the calculation of dilutive net income (loss) per share for the three and six months ended June 30, 2016 as their effect on net income (loss) per share from continuing operations was antidilutive.