15. Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Dec. 30, 2010
Accumulated Other Comprehensive Income (Loss), Beginning Balance	$ (232.0)	$ (230.7)
Change in component during the year	(1.3)
Accumulated Other Comprehensive Income (Loss), Ending Balance	(232.0)	(230.7)
As restated and amended [Member]
Accumulated Other Comprehensive Income (Loss), Beginning Balance		(230.7)	(120.7)	(156.2)
Change in component during the year			35.5
Accumulated Other Comprehensive Income (Loss), Ending Balance		(230.7)	(120.7)	(156.2)
Net Unrealized Investment Gains [Member] | As restated and amended [Member]
Accumulated Other Comprehensive Income (Loss), Beginning Balance	164.4	173.4	178.4	126.8
Change in component during the year	(9.0)		51.6
Accumulated Other Comprehensive Income (Loss), Ending Balance	164.4	173.4	178.4	126.8
Portion of OTTI Losses Recognized in OCI [Member] | As restated and amended [Member]
Accumulated Other Comprehensive Income (Loss), Beginning Balance	(96.7)	(104.5)	(96.4)	(82.5)
Change in component during the year	7.8		(13.9)
Accumulated Other Comprehensive Income (Loss), Ending Balance	(96.7)	(104.5)	(96.4)	(82.5)
Net Pension Liability Adjustments [Member] | As restated and amended [Member]
Accumulated Other Comprehensive Income (Loss), Beginning Balance	(299.7)	(299.6)	(202.7)	(200.5)
Change in component during the year	(0.1)		(2.2)
Accumulated Other Comprehensive Income (Loss), Ending Balance	$ (299.7)	$ (299.6)	$ (202.7)	$ (200.5)