Condensed Consolidated Statement of Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Operating revenues	$ 509.6	$ 485.1	$ 1,014.8	$ 980.3
Out-of-pocket reimbursements	169.9	172.0	348.5	359.2
Total revenues	679.5	657.1	1,363.3	1,339.5
Costs and expenses	576.1	551.3	1,159.8	1,125.9
Depreciation and amortization	32.1	33.1	64.1	66.3
Income from operations	71.3	72.7	139.4	147.3
Interest expense	(7.0)	(9.3)	(13.6)	(18.9)
Other income, net	131.2	28.4	224.8	101.6
Equity in earnings of unconsolidated affiliates	9.6	9.5	15.0	15.1
Income before income taxes	205.1	101.3	365.6	245.1
Income taxes	67.3	22.8	127.4	73.4
Net income	$ 137.8	$ 78.5	$ 238.2	$ 171.7
Weighted average common shares outstanding (in shares)	40.9	43.7	41.4	44.0
Weighted average diluted shares outstanding (in shares)	41.2	44.5	41.8	45.0
Basic earnings per share (in dollars per share)	$ 3.37	$ 1.80	$ 5.75	$ 3.90
Diluted earnings per share (in dollars per share)	$ 3.34	$ 1.77	$ 5.70	$ 3.81
Cash dividends per share of common stock (in dollars per share)	$ 0.30	$ 0.30	$ 0.60	$ 0.60