The cash outflow associated with amounts contributed to subsidiaries during the period.

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The total capital investment in subsidiaries during the period.

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The sale proceeds associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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The number of undisclosed insurance companies sold by the entity during the period.

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The percentage of interest acquired in subsidiaries during the period.

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Amount of direct and assumed insurance premiums written in force.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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Amount of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit, acquired at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount of operating expenses attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of operating income or loss attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the purchase of noncontrolling interest during the period.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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Acquisitions and Sales of Businesses (Details Textual) (USD $) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended			0 Months Ended	9 Months Ended	0 Months Ended
	Aug. 31, 2012 company	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Apr. 01, 2014	Dec. 31, 2014	Mar. 27, 2014	Dec. 31, 2011
Business Acquisition [Line Items]
Payments to acquire business		$ 267	$ 0	$ 0
Weighted average useful life of finite-lived intangible assets acquired		6 years
Goodwill		201us-gaap_Goodwill	185us-gaap_Goodwill	185us-gaap_Goodwill		201us-gaap_Goodwill		186us-gaap_Goodwill
Percentage of interest acquired in a subsidiary				28.00%
Purchase of interest not already owned in a subsidiary				17
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of undisclosed insurance companies sold	4
Medicare supplement and critical illness businesses [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale proceeds	326			326
Pretax gain on sale of subsidiaries	170			170
Total revenues				212
Total costs and expenses				184
Earnings before income taxes				28
Small annuity and supplemental insurance company [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale proceeds				7
Summit Holding Southeast, Inc [Member]
Business Acquisition [Line Items]
Payments to acquire business					259
Capital contributions to acquired business					140
Total capital investment in acquired business					399
Net written premiums of acquired business		539
Net earned premiums of acquired business						410
Indefinite-lived intangible assets acquired					1
Finite-lived intangible assets acquired					46
Weighted average useful life of finite-lived intangible assets acquired					7 years
Goodwill					16
Selective Insurance Company of America Self-Insured Pooled Group [Member]
Business Acquisition [Line Items]
Payments to acquire business							8
In-force gross written premiums of acquired book of business							38
Maximum [Member] \| Summit Holding Southeast, Inc [Member]
Business Acquisition [Line Items]
Expenses related to the acquisition of business (are less than)					$ 1