Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues
Clearing and transaction fees	$ 704.2	$ 715.0	$ 2,267.9	$ 2,105.0
Market data and information services	101.1	99.5	306.4	300.3
Access and communication fees	23.8	21.6	67.7	64.4
Other	12.6	14.2	40.3	43.3
Expenses	841.7	850.3	2,682.3	2,513.0
Expenses
Compensation and benefits	130.6	136.4	394.2	419.2
Communications	6.9	7.1	19.9	21.3
Technology support services	17.3	15.4	52.4	47.1
Professional fees and outside services	33.5	33.8	104.2	90.6
Amortization of purchased intangibles	24.0	24.9	72.0	74.8
Depreciation and amortization	31.2	32.4	95.5	97.5
Occupancy and building operations	19.6	23.1	65.3	69.4
Licensing and other fee agreements	31.5	33.1	103.3	92.5
Other	21.8	27.7	113.0	81.8
Total Expenses	316.4	333.9	1,019.8	994.2
Operating Income	525.3	516.4	1,662.5	1,518.8
Non-Operating Income (Expense)
Investment income	36.5	2.5	71.3	26.7
Gains (losses) on derivative investments	0.0	0.0	0.0	(1.8)
Interest and other borrowing costs	(31.1)	(28.3)	(91.9)	(88.5)
Equity in net earnings (losses) of unconsolidated subsidiaries	28.6	26.6	82.4	75.1
Other non-operating income (expense)	(10.5)	(0.8)	(30.9)	(42.0)
Total Non-Operating	23.5	0.0	30.9	(30.5)
Income before Income Taxes	548.8	516.4	1,693.4	1,488.3
Income tax provision	76.0	156.5	532.7	533.0
Net Income	$ 472.8	$ 359.9	$ 1,160.7	$ 955.3
Earnings per Common Share:
Basic (in dollars per share)	$ 1.40	$ 1.07	$ 3.44	$ 2.84
Diluted (in dollars per share)	$ 1.39	$ 1.06	$ 3.43	$ 2.83
Weighted Average Number of Common Shares:
Basic (in shares)	337,592	336,323	337,299	336,015
Diluted (in shares)	339,143	338,139	338,834	337,804