Condensed Consolidated Statement of Cash Flows (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cash flows — operating activities:
Net income	$ 268.6	$ 286.1
Depreciation and amortization	100.4	116.8
Net gains on investments	(136.5)	(220.6)
Gain on sale of properties	(5.4)	(0.6)
Amortization of share based compensation	13.9	20.1
Equity in earnings of unconsolidated affiliates	(18.9)	(9.8)
Dividends from unconsolidated affiliates	129.8	4.1
Deferred income taxes	(4.8)	(3.4)
Changes in accounts receivable	34.9	(11.3)
Changes in other assets	(7.1)	(26.4)
Changes in accounts payable and accrued liabilities	(21.6)	(25.9)
Changes in income taxes payable	(7.3)	46.5
Changes in deferred revenues and gains	(6.1)	(43.5)
Changes in accrued compensation and benefits	(10.6)	(2.6)
Other, net	4.6	9.8
Total adjustments to net income	65.3	(146.8)
Net	333.9	139.3
Cash flows — investing activities:
Capital expenditures	(75.1)	(73.4)
Investments in securities	(77.6)	(238.2)
Proceeds from sales/maturities of investments	300.0	512.2
Net (increase) decrease in restricted cash and cash equivalents held to satisfy client funds obligations	137.3	(43.8)
Proceeds from sale of properties	13.4	7.3
Other, net	(11.3)	4.8
Net	286.7	168.9
Cash flows — financing activities:
Proceeds from issuance of common stock	21.8	50.3
Principal payments on debt	(124.5)	(15.8)
Repurchases of senior convertible debentures	(122.8)	0
Net borrowings (payments) on revolving credit facilities	37.4	(275.6)
Payment of debt issuance costs	(0.2)	(0.2)
Net increase (decrease) in client funds obligations	(148.5)	56.0
Common stock repurchased	(205.1)	(30.0)
Payment for acquisition of non-controlling interest	0	(17.7)
Payment of cash dividends	(39.2)	(17.9)
Excess tax benefits from share based compensation	2.1	4.3
Net	(579.0)	(246.6)
Net increase in cash and cash equivalents	41.6	61.6
Cash and cash equivalents, beginning of period	88.3	40.9
Cash and cash equivalents, end of period	$ 129.9	$ 102.5