Ownership, Description of Business, and Summary of Significant Accounting Policies - Reconciliation of Shares Used in Calculating Earnings Per Basic and Diluted Shares (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounting Policies [Abstract]
Net (loss) income attributable to Encore Capital Group, Inc. stockholders	$ (206,492)	$ 194,564	$ 350,782
Total weighted-average basic shares outstanding (in shares)	23,670	24,142	30,129
Dilutive effect of stock-based awards (in shares)	0	344	407
Dilutive effect of convertible and exchangeable senior notes (in shares)	0	1,606	617
Total weighted-average dilutive shares outstanding (in shares)	23,670	26,092	31,153
Earnings per share
Basic (loss) income per share (usd per share)	$ (8.72)	$ 8.06	$ 11.64
Diluted (loss) income per share (usd per share)	$ (8.72)	$ 7.46	$ 11.26