Earnings (Loss) Per Share -Table and Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	May 05, 2021	Aug. 12, 2015
Subsequent Event [Line Items]
Net income (loss) attributable to Encore Capital Group, Inc. stockholders	$ 94,630	$ (10,454)
Total weighted-average basic shares outstanding (shares)	31,469,000	31,308,000
Dilutive effect of stock-based awards (shares)	363,000	0
Total weighted-average dilutive shares outstanding (shares)	31,832,000	31,308,000
Basic (loss) earnings per share (USD per share)	$ 3.01	$ (0.33)
Diluted (loss) earnings per share (USD per share)	$ 2.97	$ (0.33)
Stock Repurchase Program, Authorized Amount				$ 50,000
Stock Repurchased During Period, Shares	517,860
Repurchase of common stock	$ 20,390	$ 0
Stock Repurchased During Period, Price Per Share	$ 39.37
Antidilutive securities excluded from computation of earnings per share (shares)	13,000	13,000
Subsequent Event
Subsequent Event [Line Items]
Stock Repurchase Program, Authorized Amount			$ 300,000
Stock Repurchase Program, Increase of Authorized Amount			$ 250,000