Age at which participants could elect to remain in the defined benefit plan as of August 31, 2008.

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- Definition

Independent Insurance Agencies and Brokerages

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No definition available.

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- Definition

Number of Locations

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No definition available.

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- Definition

Number of Subsidiaries

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No definition available.

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- Definition

Percentage of earned premiums.

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No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 4

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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- Definition

The number of states the entity operates in as of the balance sheet date.

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No definition available.

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- Definition

Other investments not otherwise specified in the taxonomy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 12

-Article 5

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-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Subparagraph g

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-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(f,g))

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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- Definition

Fair value amount of the specified investment category of assets maintained in separate accounts as of the balance sheet date.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 20

-Section 55

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=6588021&loc=d3e7104-158389

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-Name Accounting Standards Codification

-Topic 944

-SubTopic 80

-Section 50

-Paragraph 1

-Subparagraph (e)

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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- Definition

Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(2)

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Summary Of Significant Accounting Policies (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 entity state	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2008
Significant Accounting Policies [Line Items]
Number of operating subsidaries	2
Number of independent insurance agencies	1,450
Number of reporting locations	1,823
Number of states in which entity operates	39
Defined Benefit Plan Qualifying Age				40 years
Depreciation expense	$ 37	$ 37	$ 46
Land, building and equipment impairments	0	0	0
Weighted-average remaining contractual life for exercisable awards	3 years 2 months 12 days
Current fair value of the BOLI invested assets and cash exceeded the current fair value of the contract holders' account value	8
Other invested assets	68	68
Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives	3 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives	39 years 6 months
Life Policy Loans [Member]
Significant Accounting Policies [Line Items]
Other invested assets	36
Venture Capital Funds [Member]
Significant Accounting Policies [Line Items]
Other invested assets	$ 32
10 Largest States [Member]
Significant Accounting Policies [Line Items]
Generated percentage of total earned premiums	63.80%	65.40%
Ohio, Largest State [Member]
Significant Accounting Policies [Line Items]
Generated percentage of total earned premiums	18.50%	19.10%
Illinois, Indiana, Pennsylvania, Georgia, North Carolina, and Michigan [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Generated percentage of total earned premiums	4.00%
Illinois, Indiana, Pennsylvania, Georgia, North Carolina, and Michigan [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Generated percentage of total earned premiums	8.00%
Largest Single Agency Relationship [Member]
Significant Accounting Policies [Line Items]
Generated percentage of total earned premiums	0.80%
All Other [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Generated percentage of total earned premiums	2.10%
Restricted Stock Units [Member]
Significant Accounting Policies [Line Items]
Awards vesting period	3 years
Stock Options [Member]
Significant Accounting Policies [Line Items]
Awards vesting period	3 years
Weighted-average remaining contractual life for exercisable awards	10 years
Property Casualty Insurance Segment [Member]
Significant Accounting Policies [Line Items]
Number of operating subsidaries	2