Segments - Results of Continuing Operations (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021		Sep. 30, 2022	Sep. 30, 2021
Segment Information
Revenue	$ 14,107.0	$ 13,251.0	[1]	$ 43,840.0	$ 40,656.0	[1]
Pre-tax income from continuing operations	(4,501.0)	813.0	[1]	(2,156.0)	1,968.0	[1]
Business Segments
Segment Information
Revenue	14,037.0	12,969.0		43,365.0	39,812.0
Pre-tax income from continuing operations	$ 2,128.0	$ 1,797.0		$ 6,470.0	$ 5,071.0
Revenue year-to-year change (as a percent)	8.20%			8.90%
Pre-tax income year-to-year change (as a percent)	18.40%			27.60%
Pre-tax income margin (as a percent)	15.20%	13.90%		14.90%	12.70%
Business Segments | Software
Segment Information
Revenue	$ 5,811.0	$ 5,406.0		$ 17,749.0	$ 16,339.0
Pre-tax income from continuing operations	$ 1,306.0	$ 990.0		$ 3,816.0	$ 2,707.0
Revenue year-to-year change (as a percent)	7.50%			8.60%
Pre-tax income year-to-year change (as a percent)	31.90%			41.00%
Pre-tax income margin (as a percent)	22.50%	18.30%		21.50%	16.60%
Business Segments | Consulting
Segment Information
Revenue	$ 4,700.0	$ 4,457.0		$ 14,337.0	$ 13,098.0
Pre-tax income from continuing operations	$ 462.0	$ 466.0		$ 1,154.0	$ 1,013.0
Revenue year-to-year change (as a percent)	5.40%			9.50%
Pre-tax income year-to-year change (as a percent)	(0.80%)			13.90%
Pre-tax income margin (as a percent)	9.80%	10.50%		8.00%	7.70%
Business Segments | Infrastructure
Segment Information
Revenue	$ 3,352.0	$ 2,921.0		$ 10,805.0	$ 9,774.0
Pre-tax income from continuing operations	$ 280.0	$ 209.0		$ 1,236.0	$ 989.0
Revenue year-to-year change (as a percent)	14.80%			10.60%
Pre-tax income year-to-year change (as a percent)	34.10%			25.00%
Pre-tax income margin (as a percent)	8.30%	7.10%		11.40%	10.10%
Business Segments | Financing
Segment Information
Revenue	$ 174.0	$ 184.0		$ 474.0	$ 601.0
Pre-tax income from continuing operations	$ 79.0	$ 132.0		$ 265.0	$ 362.0
Revenue year-to-year change (as a percent)	(5.70%)			(21.20%)
Pre-tax income year-to-year change (as a percent)	(40.40%)			(26.80%)
Pre-tax income margin (as a percent)	45.40%	71.70%		55.90%	60.10%

[1] Reclassified to reflect discontinued operations presentation.