Consolidated Statements of Financial Position (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
CURRENT ASSETS
Cash and cash equivalents	$ 291	$ 272
Short-term investments	346	785
Receivables, net	3,101	3,183
Fiduciary assets	12,214	10,838
Other current assets	430	427
Total Current Assets	16,382	15,505
Goodwill	8,943	8,770
Intangible assets, net	2,975	3,276
Fixed assets, net	820	783
Investments	165	239
Deferred tax assets	285	258
Other non-current assets	916	721
TOTAL ASSETS	30,486	29,552
CURRENT LIABILITIES
Fiduciary liabilities	12,214	10,838
Short-term debt and current portion of long-term debt	452	337
Accounts payable and accrued liabilities	1,853	1,832
Other current liabilities	831	753
Total Current Liabilities	15,350	13,760
Long-term debt	3,713	4,155
Deferred tax liabilities	306	301
Pension, other post retirement, and post employment liabilities	2,276	2,192
Other non-current liabilities	1,036	1,024
TOTAL LIABILITIES	22,681	21,432
EQUITY
Ordinary shares (2012 - $0.01 nominal value; 2011 - $1.00 par value) Authorized: 750 shares (issued: 2012 - 310.9; 2011 - 386.4)	3	386
Additional paid-in capital	4,436	4,021
Retained earnings	5,933	8,594
Treasury shares at cost (shares: 2012 - 0; 2011 - 61.6)		(2,553)
Accumulated other comprehensive loss	(2,610)	(2,370)
TOTAL AON SHAREHOLDERS' EQUITY	7,762	8,078
Noncontrolling interests	43	42
TOTAL EQUITY	7,805	8,120
TOTAL LIABILITIES AND EQUITY	$ 30,486	$ 29,552