Investment Securities (Mortgage-backed Asset Securities) (Details) (USD $)	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Level 2 Inputs
Investment securities
Fair value investments	$ 4,982,200,000		$ 5,206,100,000		$ 6,088,200,000
Level 2 Inputs | GNMA
Investment securities
Fair value investments	512,300,000		1,013,400,000
Level 2 Inputs | FNMA
Investment securities
Fair value investments	81,200,000		74,600,000
Level 2 Inputs | FHLMC
Investment securities
Fair value investments	91,300,000		55,800,000
Level 2 Inputs | Total Agency
Investment securities
Fair value investments	684,800,000	[1]	1,143,800,000	[1]
Level 2 Inputs | Residential
Investment securities
Fair value investments	125,700,000		160,600,000
Level 2 Inputs | Commercial
Investment securities
Fair value investments	282,300,000		334,100,000
Level 2 Inputs | Total Non-agency
Investment securities
Fair value investments	408,000,000		494,700,000
Level 2 Inputs | Total mortgage-backed securities
Investment securities
Fair value investments	1,092,800,000		1,638,500,000
Level 2 Inputs | Credit card receivables
Investment securities
Fair value investments	289,400,000		151,400,000
Level 2 Inputs | Vehicle receivables
Investment securities
Fair value investments	365,000,000		233,200,000
Level 2 Inputs | Other
Investment securities
Fair value investments	245,300,000		50,400,000
Level 2 Inputs | Total asset-backed securities
Investment securities
Fair value investments	899,700,000		435,000,000
Level 2 Inputs | Total mortgage and asset- backed securities
Investment securities
Fair value investments	1,992,500,000		2,073,500,000
Level 3 Inputs | GNMA
Investment securities
Fair value investments	0		0
Level 3 Inputs | FNMA
Investment securities
Fair value investments	0		0
Level 3 Inputs | FHLMC
Investment securities
Fair value investments	0		0
Level 3 Inputs | Total Agency
Investment securities
Fair value investments	0	[1]	0	[1]
Level 3 Inputs | Residential
Investment securities
Fair value investments	0		0
Level 3 Inputs | Commercial
Investment securities
Fair value investments	0		0
Level 3 Inputs | Total Non-agency
Investment securities
Fair value investments	0		0
Level 3 Inputs | Total mortgage-backed securities
Investment securities
Fair value investments	0		0
Level 3 Inputs | Credit card receivables
Investment securities
Fair value investments	22,000,000		22,100,000
Level 3 Inputs | Vehicle receivables
Investment securities
Fair value investments	0		0
Level 3 Inputs | Other
Investment securities
Fair value investments	0		0
Level 3 Inputs | Total asset-backed securities
Investment securities
Fair value investments	22,000,000		22,100,000
Level 3 Inputs | Total mortgage and asset- backed securities
Investment securities
Fair value investments	22,000,000		22,100,000
Fair value
Investment securities
Fair value investments	6,766,500,000	[2],[3],[4]	6,950,700,000	[2],[3],[4],[5],[6],[7]	7,500,800,000	[5],[6],[7]
Fair value | GNMA
Investment securities
Fair value investments	512,300,000		1,013,400,000
Fair value | FNMA
Investment securities
Fair value investments	81,200,000		74,600,000
Fair value | FHLMC
Investment securities
Fair value investments	91,300,000		55,800,000
Fair value | Total Agency
Investment securities
Fair value investments	684,800,000	[1]	1,143,800,000	[1]
Fair value | Residential
Investment securities
Fair value investments	125,700,000		160,600,000
Fair value | Commercial
Investment securities
Fair value investments	282,300,000		334,100,000
Fair value | Total Non-agency
Investment securities
Fair value investments	408,000,000		494,700,000
Fair value | Total mortgage-backed securities
Investment securities
Fair value investments	1,092,800,000		1,638,500,000
Fair value | Credit card receivables
Investment securities
Fair value investments	311,400,000		173,500,000
Fair value | Vehicle receivables
Investment securities
Fair value investments	365,000,000		233,200,000
Fair value | Other
Investment securities
Fair value investments	245,300,000		50,400,000
Fair value | Total asset-backed securities
Investment securities
Fair value investments	921,700,000		457,100,000
Fair value | Total mortgage and asset- backed securities
Investment securities
Fair value investments	2,014,500,000		2,095,600,000
Fair value | Non-Agency Residential Mortgage
Investment securities
Fair value investments	$ 0

[1] Represents publicly traded mortgage-backed securities which carry the full faith and credit guaranty of the U.S. government (i.e., GNMA) or are guaranteed by a government sponsored entity (i.e., FNMA, FHLMC).

[2] Excludes carrying value of $26.6 and $35.0 at December 31, 2013 and January 1, 2013 associated with other long-term investments accounted for using the equity method and $(.1) at December 31, 2013 related to currency forward contracts.

[3] Excludes carrying value of $635.9 and $630.6 at December 31, 2013 and January 1, 2013 classified as short-term investments.

[4] Carrying value includes $236.3 and $338.1 at December 31, 2013 and January 1, 2013 that is classified as assets held for sale relating to discontinued operations.

[5] Carrying value includes $338.1 and $111.8 at December 31, 2012 and January 1, 2012 that is classified as assets held for sale relating to AutoOne discontinued operations.

[6] Excludes carrying value of $35.0 and $33.0 at December 31, 2012 and January 1, 2012 associated with other long-term investment limited partnerships accounted for using the equity method and $(.1) at December 31, 2012 related to currency forward contracts.

[7] Excludes carrying value of $630.6 and $846.0 at December 31, 2012 and January 1, 2012 classified as short-term investments.