Commitments and Contingent Liabilities Reinsurance and Retention Limits (Details) (USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Reinsurance Premiums for Insurance Companies, by Product Segment
Reinsurance Unrecoverable Amount	$ 21,200,000		$ 21,200,000
General Insurance Group [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment
Workers Compensation Insurance, Maximum Coverage Limit	5,200,000
Commercial Auto Liability Compensation Insurance, Maximum Coverage Limit	3,500,000
General Liabiltity Insurance, Maximum Coverage Limit	3,500,000
Executive Protection Insurance, Maximum Coverage Limit	8,000,000
Aviation Insurance, Maximum Coverage Limit	2,000,000
Property Coverages Insurance, Maximum Coverage Limit	4,000,000
Workers Compensation, Coverage Limit	200,000,000
Reinsurance Limits	198,000,000
Reinsurance Limits for Acts of Terrorism	2,000,000
Reinsurance Recoverable, Concentration Risk Ten Largest Insurers, Percentage	59.00%
Reinsurance Recoverable, Concentration Risk Largest Insurer, Percentage	27.70%
Reinsurance Recoverable, Concentration Risk Ten Largest Insurers, Percentage of A Rating or Better	84.50%
Reinsurance Recoverable Concentration Risk Ten Largest Insurers Percentage of B Plus Rating	3.20%
Reinsurance Recoverable, Concentration Risk Ten Largest Insurers, Percentage From Industry-Wide Risk Pools	6.00%
Reinsurance Recoverable, Concentration Risk Ten Largest Insurers, Percentage From Foreign Unrated Companies	6.30%
Direct Premiums Written	3,348,100,000	[1]	3,043,400,000	[1]	2,763,000,000	[1]
Assumed Premiums Written	28,800,000	[1]	19,900,000	[1]	6,100,000	[1]
Ceded Premiums Written	775,800,000	[1]	696,500,000	[1]	631,500,000	[1]
Direct Premiums Earned	3,235,700,000	[1]	2,949,900,000	[1]	2,716,200,000	[1]
Assumed Premiums Earned	24,100,000	[1]	17,900,000	[1]	8,900,000	[1]
Ceded Premiums Earned	746,100,000	[1]	643,400,000	[1]	615,800,000	[1]
Reinsurance Effect on Claims and Benefits Incurred, Amount Ceded	469,500,000	[1]	410,600,000	[1]	427,000,000	[1]
RFIG Run-off Business [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment
Mortgage Guaranty Insurance, Subjected to Reinsurance Arrangements, Percentage	0.10
Average Direct Primary Mortgage Guaranty Exposure, Per Insured Loan	38,697
Claims Exposure, Concentration Risk, Largest Insurer, Amount	10.5
Reinsured Liabilities, Concentration Risk Largest Insurer, Percentage	0.40%
Direct Premiums Written	314,300,000	[1]	409,200,000	[1]	544,400,000	[1]
Assumed Premiums Written	0	[1]	0	[1]	0	[1]
Ceded Premiums Written	9,900,000	[1]	19,300,000	[1]	23,200,000	[1]
Direct Premiums Earned	326,400,000	[1]	429,800,000	[1]	526,400,000	[1]
Assumed Premiums Earned	0	[1]	0	[1]	100,000	[1]
Ceded Premiums Earned	9,900,000	[1]	19,300,000	[1]	23,200,000	[1]
Reinsurance Effect on Claims and Benefits Incurred, Amount Ceded	3,400,000	[1]	24,200,000	[1]	42,200,000	[1]
Insurance in force, direct	43,994,500,000		56,413,700,000		70,520,900,000
Insurance in force, assumed	0		0		446,000,000
Insurance in force, ceded	460,400,000		886,100,000		1,452,700,000
Title Insurance Group [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment
Title Insurance Risk, Per Policy	500,000,000
Title Insurance Risk Exposure, Per Policy	$ 1,000,000

[1] As previously noted, consumer credit indemnity coverages are reported within the RFIG Run-off segment and have been excluded from the General Insurance Group for all periods presented to conform with segment classifications adopted in 2012. See Note 6.