v3.26.3
Document and Entity Information
Sep. 18, 2026
Document And Entity Information [Line Items]  
Amendment Flag false
Entity Central Index Key 0000315293
Document Type 8-K
Document Period End Date Sep. 18, 2026
Entity Registrant Name Aon plc
Entity Incorporation State Country Code L2
Entity File Number 1-7933
Entity Tax Identification Number 98-1539969
Entity Address, Address Line One 15 George’s Quay
Entity Address, City or Town Dublin 2
Entity Address, Country IE
Entity Address, Postal Zip Code D02 VR98
City Area Code 353 1
Local Phone Number 266 6000
Written Communications false
Soliciting Material false
Pre Commencement Tender Offer false
Pre Commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Capital Unit, Class A [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Class A Ordinary Shares $0.01 nominal value
Trading Symbol AON
Security Exchange Name NYSE
Guarantees Of Aon Corporation And Aon Global Holdings Plcs 285 Senior Notes Due 2027 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.85% Senior Notes due 2027
Trading Symbol AON27
Security Exchange Name NYSE
Guarantees Of Aon Corporation And Aon Global Holdings Plcs 2.05 Senior Notes Due 203110 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.05% Senior Notes due 2031
Trading Symbol AON31
Security Exchange Name NYSE
Guarantees Of Aon Corporation And Aon Global Holdings Plcs 2.60 Senior Notes Due 20311 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.60% Senior Notes due 2031
Trading Symbol AON31A
Security Exchange Name NYSE
Guarantees Of Aon Corporation And Aon Global Holdings Plcs 5.00 Senior Notes Due 20322 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon Corporation and Aon Global Holdings plc’s 5.00% Senior Notes due 2032
Trading Symbol AON32
Security Exchange Name NYSE
Guarantees Of Aon Corporation And Aon Global Holdings Plcs 5.35 Senior Notes Due 20333 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon Corporation and Aon Global Holdings plc’s 5.35% Senior Notes due 2033
Trading Symbol AON33
Security Exchange Name NYSE
Guarantees Of Aon Plcs 4.25 Senior Notes Due 2042 Member 14 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon plc’s 4.25% Senior Notes due 2042
Trading Symbol AON42
Security Exchange Name NYSE
Guarantees Of Aon Plcs 4.45 Senior Notes Due 204311 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon plc’s 4.45% Senior Notes due 2043
Trading Symbol AON43
Security Exchange Name NYSE
Guarantees Of Aon Plcs 4.60 Senior Notes Due 204412 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon plc’s 4.60% Senior Notes due 2044
Trading Symbol AON44
Security Exchange Name NYSE
Guarantees Of Aon Plcs 4.75 Senior Notes Due 204513 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon plc’s 4.75% Senior Notes due 2045
Trading Symbol AON45
Security Exchange Name NYSE
Guarantees Of Aon Corporation And Aon Global Holdings Plcs 2.90 Senior Notes Due 20514 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.90% Senior Notes due 2051
Trading Symbol AON51
Security Exchange Name NYSE
Guarantees Of Aon Corporation And Aon Global Holdings Plcs 390 Senior Notes Due 2052 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon Corporation and Aon Global Holdings plc’s 3.90% Senior Notes due 2052
Trading Symbol AON52
Security Exchange Name NYSE
Guarantees Of Aon North America Inc .s 5.125 Senior Notes Due 2027 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc.’s 5.125% Senior Notes due 2027
Trading Symbol AON27B
Security Exchange Name NYSE
Guarantees Of Aon North America Inc .s 5.150 Senior Notes Due 2029 Member 16 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc.’s 5.150% Senior Notes due 2029
Trading Symbol AON29
Security Exchange Name NYSE
Guarantees Of Aon North America Inc .s 5.300 Senior Notes Due 2031 Member 18 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc.’s 5.300% Senior Notes due 2031
Trading Symbol AON31B
Security Exchange Name NYSE
Guarantees Of Aon North America Inc .s 5.450 Senior Notes Due 2034 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc.’s 5.450% Senior Notes due 2034
Trading Symbol AON34
Security Exchange Name NYSE
Guarantees Of Aon North America Inc .s 5.750 Senior Notes Due 2054 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc.’s 5.750% Senior Notes due 2054
Trading Symbol AON54
Security Exchange Name NYSE
Guarantees Of Aon North America Inc . And Aon Global Holdings Plcs 5.350 Senior Notes Due 202915 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc. and Aon Global Holdings plc’s 5.350% Senior Notes due 2029
Trading Symbol AON29B
Security Exchange Name NYSE
Guarantees Of Aon North America Inc . And Aon Global Holdings Plcs 5.625 Senior Notes Due 203117 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc. and Aon Global Holdings plc’s 5.625% Senior Notes due 2031
Trading Symbol AON31C
Security Exchange Name NYSE
Guarantees Of Aon North America Inc . And Aon Global Holdings Plcs 5.800 Senior Notes Due 20335 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc. and Aon Global Holdings plc’s 5.800% Senior Notes due 2033
Trading Symbol AON33A
Security Exchange Name NYSE
Guarantees Of Aon North America Inc . And Aon Global Holdings Plcs 5.950 Senior Notes Due 20366 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc. and Aon Global Holdings plc’s 5.950% Senior Notes due 2036
Trading Symbol AON36
Security Exchange Name NYSE
Guarantees Of Aon North America Inc . And Aon Global Holdings Plcs 6.100 Senior Notes Due 20387 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc. and Aon Global Holdings plc’s 6.100% Senior Notes due 2038
Trading Symbol AON38
Security Exchange Name NYSE
Guarantees Of Aon North America Inc . And Aon Global Holdings Plcs 6.450 Senior Notes Due 20468 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc. and Aon Global Holdings plc’s 6.450% Senior Notes due 2046
Trading Symbol AON46
Security Exchange Name NYSE
Guarantees Of Aon North America Inc . And Aon Global Holdings Plcs 6.450 Senior Notes Due 20569 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Guarantees of Aon North America, Inc. and Aon Global Holdings plc’s 6.450% Senior Notes due 2056
Trading Symbol AON56
Security Exchange Name NYSE