CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Condensed Statement of Income Captions [Line Items]
Income (loss) from continuing operations	$ (14,292)	$ 1,988	$ 28,601
Other comprehensive income (loss) from discontinued operations - foreign currency translation adjustments:
Comprehensive income (loss)	(7,216)	4,585	419
Comprehensive income attributable to noncontrolling interests	(10,682)	(13,067)	(12,587)
Comprehensive income (loss) attributable to Groupon, Inc.	(17,898)	(8,482)	(12,168)
Continuing Operations
Condensed Statement of Income Captions [Line Items]
Income (loss) from continuing operations	(14,292)	1,988	28,601
Other comprehensive income (loss) from continuing operations:
Net change in unrealized gain (loss) on foreign currency translation adjustments	4,858	3,332	(10,776)
Net change in unrealized gain (loss) on defined benefit pension plan	0	0	585
Net unrealized gain (loss) during the period	(379)	(841)	(1,109)
Reclassification adjustment for realized (gain) loss on investment included in income (loss) from continuing operations	0	106	1,603
Net change in unrealized gain (loss) on available-for-sale securities	(379)	(735)	494
Other comprehensive income (loss) from discontinued operations - foreign currency translation adjustments:
Other comprehensive income (loss)	4,479	2,597	(9,697)
Comprehensive income (loss)	(9,813)	4,585	18,904
Discontinued Operations, Disposed of by Sale
Other comprehensive income (loss) from continuing operations:
Net change in unrealized gain (loss) on available-for-sale securities	0	0	(16,511)
Income (loss) from discontinued operations	2,597	0	(1,974)
Other comprehensive income (loss) from discontinued operations - foreign currency translation adjustments:
Net unrealized gain (loss) during the period	0	0	(1,793)
Reclassification adjustment included in income (loss) from discontinued operations	0	0	(14,718)
Other comprehensive income (loss)	$ 2,597	$ 0	$ (18,485)