8. Investing Activities (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Sep. 30, 2011 As restated and amended [Member]	Sep. 30, 2011 As restated and amended [Member]
Balance, beginning of period	$ (78.8)	$ (79.1)	$ (70.8)	$ (65.8)
Add: Credit losses on securities not previously impaired	(1.5)	(3.8)	(3.4)	(9.1)
Add: Credit losses on securities previously impaired	(5.6)	(11.8)	(2.4)	(4.6)
Less: Credit losses on securities impaired due to intent to sell
Less: Credit losses on securities sold	5.3	14.1	4.0	6.9
Less: Increases in cash flows expected on previously impaired securities
Balance, end of period	$ (80.6)	$ (80.6)	$ (72.6)	$ (72.6)