Investments (Tables)

9 Months Ended

Sep. 30, 2013

Investments, Debt and Equity Securities [Abstract]

Schedule of investments

Investments are as follows (in millions): 

	Carrying Value
	September 30, 2013		December 31, 2012
Available-for-sale securities:
State Street Corporation	$	518.2	$	436.3
Other available-for-sale securities	137.7		175.2
	655.9		611.5
Other:
Trading securities	41.8		46.8
Held-to-maturity	—		14.9
Cost method, private equity and other investments	214.5		248.9
	256.3		310.6
Total investments	$	912.2	$	922.1

Schedule of reconciliation of available-for-sale securities from book cost basis to market value

Certain information related to the Company’s available-for-sale securities is as follows (in millions):

	September 30, 2013			December 31, 2012
Book cost basis	$	179.4		$	200.9
Gross unrealized gains	477.2			412.5
Gross unrealized losses	(0.7		)	(1.9		)
Market value	$	655.9		$	611.5

Schedule of fair value and gross unrealized losses of investments by length of time in a continuous loss position

The following table summarizes the fair value and gross unrealized losses of the Company’s investments by the length of time that the securities have been in a continuous loss position, at September 30, 2013 and December 31, 2012 (in millions):

	Less than 12 months				Greater than 12 months				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
September 30, 2013
Common stock	$	19.7	$	0.7	$	—	$	—	$	19.7	$	0.7
December 31, 2012
Common stock	$	25.7	$	1.9	$	—	$	—	$	25.7	$	1.9