Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 551.5	$ 281.2	$ 143.4
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of fixed assets and intangible assets	150.9	148.4	169.9
Provision for uncollectible receivables	10.4	10.7	19.3
Amortization of restricted stock and other non-cash compensation	51.7	50.0	49.5
Net amortization of bond (premiums) discounts and deferred financing costs	(8.7)	(4.4)	12.1
Deferred income tax provision	83.9	56.0	89.2
Gain on sale of an investment	(132.2)	0	0
Loss on early extinguishment of debt	0	0.1	25.1
Other	28.2	24.9	13.4
Changes in assets and liabilities, net of acquisitions and dispositions, providing (using) cash:
Accounts receivable	(219.2)	(547.6)	179.5
Expenditures billable to clients	(39.2)	(122.8)	19.7
Other current assets	(42.0)	(0.2)	33.1
Accounts payable	(62.9)	867.4	230.0
Accrued liabilities	3.9	66.4	(363.4)
Other non-current assets and liabilities	(102.8)	(12.8)	(80.0)
Net cash provided by operating activities	273.5	817.3	540.8
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from the sale of an investment	133.5	0	0
Acquisitions, including deferred payments, net of cash acquired	(63.1)	(61.9)	(72.4)
Capital expenditures	(140.3)	(96.3)	(67.1)
Net (purchases) sales and maturities of short-term marketable securities	(0.7)	(2.5)	158.5
Other investing activities	11.8	52.2	10.4
Net cash (used in) provided by investing activities	(58.8)	(108.5)	29.4
CASH FLOWS FROM FINANCING ACTIVITIES:
Repurchase of common stock	(400.8)	0	0
Common stock dividends	(111.1)	0	0
Repurchase of preferred stock	0	(265.9)	0
Purchase of long-term debt	(38.9)	(217.3)	(783.4)
Proceeds from issuance of 10.00% Senior Notes due 2017	0	0	587.7
Net increase in short term bank borrowings	42.5	17.4	0
Acquisition-related payments	(71.5)	(29.5)	(5.9)
Distributions to noncontrolling interests	(23.0)	(21.5)	(22.2)
Preferred stock dividends	(11.6)	(19.6)	(27.6)
Other financing activities	73.4	(11.3)	(15.6)
Net cash used in financing activities	(541.0)	(547.7)	(267.0)
Effect of foreign exchange rate changes on cash and cash equivalents	(46.7)	19.4	84.8
Net (decrease) increase in cash and cash equivalents	(373.0)	180.5	388.0
Cash and cash equivalents at beginning of period	2,675.7	2,495.2	2,107.2
Cash and cash equivalents at end of period	$ 2,302.7	$ 2,675.7	$ 2,495.2