Number of Industries Operated In

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Number of Insurance Segments

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of fees and commissions from financial services and banking activities and correspondent clearing. Includes fees from depositor accounts, credit cards, merchant discounts, and fiduciary and trust activities, guarantee fees, investment advisory, management, and administrative fees, transfer agent fees, and insurance commissions.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Amount of revenue and income classified as other.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Segment Information (Details) $ in Millions	3 Months Ended								12 Months Ended
Segment Information (Details) $ in Millions	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment industry	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information
Earned premiums									$ 4,954	$ 4,710	$ 4,480
Total revenues	$ 1,411	$ 1,412	$ 1,386	$ 1,523	$ 1,312	$ 1,402	$ 1,371	$ 1,364	5,732	5,449	5,142
Other Income									5	5	7
Fees and Commissions									16	15	13
Net Investment Income									609	595	572
Realized investment gains, net									148	124	70
Income before income taxes	197	$ 129	$ 128	$ 276	128	$ 253	$ 166	$ 265	730	812	881
Identifiable assets	21,843				20,386				$ 21,843	20,386
Number of Industries Operated In \| industry									2
Number of Insurance Segments \| segment									4
Life Insurance Segment
Segment Reporting Information
Earned premiums									$ 232	228	209
Identifiable assets	1,409				1,366				1,409	1,366
Investments Segment
Segment Reporting Information
Identifiable assets	17,112				15,569				17,112	15,569
Consolidated Property and Casualty Insurance Entity
Segment Reporting Information
Identifiable assets	2,863				2,967				2,863	2,967
Corporate and Other [Member]
Segment Reporting Information
Identifiable assets	$ 459				$ 484				459	484
Operating Segments \| Commercial Insurance
Segment Reporting Information
Earned premiums									3,165	3,089	2,996
Total revenues									3,170	3,094	3,000
Fees and Commissions									5	5	4
Income before income taxes									119	184	345
Operating Segments \| Commercial Insurance \| Commercial Casualty Line
Segment Reporting Information
Earned premiums									1,072	1,050	1,010
Operating Segments \| Commercial Insurance \| Commercial Property Line
Segment Reporting Information
Earned premiums									903	867	815
Operating Segments \| Commercial Insurance \| Commercial Auto Line
Segment Reporting Information
Earned premiums									634	594	561
Operating Segments \| Commercial Insurance \| Workers' Compensation Line
Segment Reporting Information
Earned premiums									335	354	367
Operating Segments \| Commercial Insurance \| Other Commercial Lines
Segment Reporting Information
Earned premiums									221	224	243
Operating Segments \| Personal Insurance
Segment Reporting Information
Earned premiums									1,241	1,161	1,097
Total revenues									1,246	1,165	1,100
Fees and Commissions									5	4	3
Income before income taxes									(32)	(12)	(12)
Operating Segments \| Personal Insurance \| Personal Auto
Segment Reporting Information
Earned premiums									582	543	506
Operating Segments \| Personal Insurance \| Home Owner Line
Segment Reporting Information
Earned premiums									518	486	463
Operating Segments \| Personal Insurance \| Other Personal Lines
Segment Reporting Information
Earned premiums									141	132	128
Operating Segments \| Excess and Surplus Lines Insurance
Segment Reporting Information
Earned premiums									209	183	168
Total revenues									210	184	169
Fees and Commissions									1	1	1
Income before income taxes									61	62	51
Operating Segments \| Life Insurance Segment
Segment Reporting Information
Earned premiums									232	228	209
Total revenues									237	233	214
Fees and Commissions									5	5	5
Income before income taxes									(1)	1	(2)
Operating Segments \| Investments Segment
Segment Reporting Information
Total revenues									757	719	642
Net Investment Income									609	595	572
Realized investment gains, net									148	124	70
Income before income taxes									664	629	556
Corporate, Non-Segment [Member]
Segment Reporting Information
Total revenues									112	54	17
Corporate, Non-Segment [Member] \| Reinsurance assumed and other non segment [Member]
Segment Reporting Information
Earned premiums									107	49	10
Corporate, Non-Segment [Member] \| Corporate and Other [Member]
Segment Reporting Information
Other Income									5	5	7
Income before income taxes									$ (81)	$ (52)	$ (57)