Other Comprehensive Income (Tables)

6 Months Ended

Jun. 30, 2012

Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]

Schedule of changes in balances of each component of accumulated other comprehensive income

Three Months Ended June 30, 2012

	Net Unrealized Gains (Losses) on Investments		Cumulative Translation Adjustment			Cash Flow Hedge			Total Accumulated Other Comprehensive Income
	(in millions)
Balance, March 31, 2012	$	395.9	$	(6.8	)	$	9.3		$	398.4
Other comprehensive income (loss)	32.3		(1.2		)	(0.1		)	31.0
Balance, June 30, 2012	$	428.2	$	(8.0	)	$	9.2		$	429.4

Three Months Ended June 30, 2011

	Net Unrealized Gains (Losses) on Investments		Cumulative Translation Adjustment			Cash Flow Hedge			Total Accumulated Other Comprehensive Income
	(in millions)
Balance, March 31, 2011	$	83.2	$	(6.5	)	$	9.7		$	86.4
Other comprehensive income (loss)	119.0		0.3			(0.1		)	119.2
Balance, June 30, 2011	$	202.2	$	(6.2	)	$	9.6		$	205.6

Six Months Ended June 30, 2012

	Net Unrealized Gains (Losses) on Investments		Cumulative Translation Adjustment			Cash Flow Hedge			Total Accumulated Other Comprehensive Income
	(in millions)
Balance, December 31, 2011	$	366.7	$	(8.6	)	$	9.4		$	367.5
Other comprehensive income (loss)	61.5		0.6			(0.2		)	61.9
Balance, June 30, 2012	$	428.2	$	(8.0	)	$	9.2		$	429.4

Six Months Ended June 30, 2011

	Net Unrealized Gains (Losses) on Investments		Cumulative Translation Adjustment			Cash Flow Hedge			Total Accumulated Other Comprehensive Income
	(in millions)
Balance, December 31, 2010	$	109.7	$	(7.7	)	$	9.8		$	111.8
Other comprehensive income (loss)	92.5		1.5			(0.2		)	93.8
Balance, June 30, 2011	$	202.2	$	(6.2	)	$	9.6		$	205.6