REVENUE - Schedule of Revenue Streams (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Disaggregation of Revenue [Line Items]
Total revenue	$ 393,359	$ 381,350	$ 1,244,048	$ 1,241,495
Pega Cloud
Disaggregation of Revenue [Line Items]
Total revenue	218,925	184,549	637,890	502,415
Maintenance
Disaggregation of Revenue [Line Items]
Total revenue	72,653	79,649	222,498	235,288
Consulting
Disaggregation of Revenue [Line Items]
Total revenue	46,203	56,394	151,202	174,639
Subscription
Disaggregation of Revenue [Line Items]
Total revenue	347,156	324,956	1,092,846	1,066,856
Subscription services
Disaggregation of Revenue [Line Items]
Total revenue	291,578	264,198	860,388	737,703
Subscription license
Disaggregation of Revenue [Line Items]
Total revenue	55,578	60,758	232,458	329,153
Revenue recognized over time
Disaggregation of Revenue [Line Items]
Total revenue	337,781	320,592	1,011,590	912,342
Revenue recognized over time \| Pega Cloud
Disaggregation of Revenue [Line Items]
Total revenue	218,925	184,549	637,890	502,415
Revenue recognized over time \| Maintenance
Disaggregation of Revenue [Line Items]
Total revenue	72,653	79,649	222,498	235,288
Revenue recognized over time \| Consulting
Disaggregation of Revenue [Line Items]
Total revenue	46,203	56,394	151,202	174,639
Revenue recognized at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	55,578	60,758	232,458	329,153
Revenue recognized at a point in time \| Subscription license
Disaggregation of Revenue [Line Items]
Total revenue	$ 55,578	$ 60,758	$ 232,458	$ 329,153