Revenue - Disaggregated Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 531	$ 603	$ 1,118	$ 1,221
Point in time
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	17	18	36	37
Over time
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	514	585	1,082	1,184
Commercial:
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	316	365	677	767
Commercial: \| Customer Experience Management
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	91	122	210	266
Commercial: \| BPaaS
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	114	115	229	232
Commercial: \| Integrated Digital Solutions
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	111	128	238	269
Government:
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	215	238	441	454
Government: \| Government Healthcare Solutions
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	117	137	254	263
Government: \| Government Services Solutions
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 98	$ 101	$ 187	$ 191