Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Sep. 30, 2012		Dec. 31, 2011
Assets
Cash and cash equivalents	$ 2,016.9		$ 1,042.3
Marketable securities	62.0		47.6
Accounts receivable, net of allowance of $1.7 and $1.3	296.9		289.4
Other current assets (includes $40.0 in restricted cash)	245.7		232.6
Cash performance bonds and guaranty fund contributions	7,395.3		9,333.9
Total current assets	10,016.8		10,945.8
Property, net of accumulated depreciation and amortization of $611.5 and $576.3	705.4		821.9
Intangible assets - trading products	17,040.5	[1]	17,040.5	[1]
Intangible assets - other, net	2,879.5		3,312.8
Goodwill	7,538.3		7,984.0
Other assets (includes $20.5 in restricted cash)	1,677.5		653.7
Total Assets	39,858.0		40,758.7
Liabilities and Shareholders' Equity
Accounts payable	44.5		31.1
Short-term debt	749.6		0
Other current liabilities	200.1		250.2
Cash performance bonds and guaranty fund contributions	7,395.3		9,333.9
Total current liabilities	8,389.5		9,615.2
Long-term debt	2,106.4		2,106.8
Deferred income tax liabilities, net	7,319.8		7,226.8
Other liabilities	254.1		187.6
Total Liabilities	18,069.8		19,136.4
Redeemable non-controlling interest	79.4		70.3
Shareholders' Equity:
Preferred stock, $0.01 par value, 10,000 and 9,860 shares authorized, none issued or outstanding	0		0
Series A junior participating preferred stock, $0.01 par value, 0 and 140 shares authorized, none issued or outstanding	0		0
Additional paid-in capital	17,177.2		17,112.5
Retained earnings	4,408.6		4,324.6
Accumulated other comprehensive income (loss)	119.7		111.6
Total Shareholders' Equity	21,708.8		21,552.0
Total Liabilities and Shareholders' Equity	39,858.0		40,758.7
Class A Common Stock [Member]
Shareholders' Equity:
Common stock	3.3		3.3
Class B Common Stock [Member]
Shareholders' Equity:
Common stock	$ 0		$ 0

[1] Trading products represent futures and options products acquired in our business combinations with CBOT Holdings, Inc. (CBOT Holdings) and NYMEX Holdings, Inc. (NYMEX Holdings). Clearing and transaction fees revenues are generated through the trading of these products. These trading products, most of which have traded for decades, require authorization from the Commodity and Futures Trading Commission (CFTC). Product authorizations from the CFTC have no term limits.