Condensed Consolidated Statements of Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Revenue
Total revenue	$ 3,997	$ 3,721	$ 12,881	$ 11,551
Expenses
Compensation and benefits	2,259	2,150	6,868	6,163
Information technology	140	141	412	397
Premises	85	88	252	241
Depreciation of fixed assets	47	47	140	136
Amortization and impairment of intangible assets	193	174	593	318
Other general expense	425	429	1,244	1,232
Accelerating Aon United Program expenses	32	69	236	320
Total operating expenses	3,181	3,098	9,745	8,807
Operating income	816	623	3,136	2,744
Interest income	0	4	5	63
Interest expense	(206)	(213)	(624)	(582)
Other income (expense)	(13)	35	33	346
Income before income taxes	597	449	2,550	2,571
Income tax expense	127	94	504	585
Net income	470	355	2,046	1,986
Less: Net income attributable to redeemable and nonredeemable noncontrolling interests	12	12	44	48
Net income attributable to Aon shareholders	$ 458	$ 343	$ 2,002	$ 1,938
Basic net income per share attributable to Aon shareholders (in dollars per share)	$ 2.12	$ 1.58	$ 9.26	$ 9.24
Diluted net income per share attributable to Aon shareholders (in dollars per share)	$ 2.11	$ 1.57	$ 9.21	$ 9.20
Weighted average ordinary shares outstanding - basic (in shares)	215.7	217.4	216.1	209.7
Weighted average ordinary shares outstanding - diluted (in shares)	216.7	218.4	217.3	210.6