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Offer Price Per Share

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Percentage Of Ownership Interest Before Sale Of Partnership Units

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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Basis Of Presentation (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended			9 Months Ended				0 Months Ended						9 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2011	Jun. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Maximum [Member]	Sep. 30, 2011 Minimum [Member]	Aug. 11, 2011 CNA Financial Corporation [Member]	Sep. 30, 2011 CNA Financial Corporation [Member]	Sep. 30, 2011 Diamond Offshore Drilling, Inc. [Member]	Sep. 30, 2011 HighMount Exploration & Production LLC [Member]	Sep. 30, 2011 Boardwalk Pipeline Partners LP [Member]	Sep. 30, 2011 Loews Hotels Holding Corporation [Member]	Sep. 30, 2011 CNA Surety [Member]	Sep. 30, 2011 FICOH [Member]	Sep. 30, 2011 FICOH [Member]
Basis Of Presentation [Line Items]
Ownership percentage in subsidiary								50.00%	90.00%	50.40%	100.00%	64.00%	100.00%	61.00%
Stock options and stock appreciation rights not included in diluted weighted average shares amount	3.2		2.1	2.6	2.6
Sale of noncontrolling interest								50.00%
Income tax expense	$ 124		$ 84	$ 464	$ 619										$ 22	$ 22
Units sold in public offering		6
Proceeds from subsidiary public offering		170
Company ownership interest before public offering												66.00%
Aggregate purchase price														475
Offer price per share														$ 26.55
Amount paid to acquire noncontrolling interest														438
Adjusted to additional paid-in capital														54
Increase in accumulated other comprehensive income related to acquisition of noncontrolling interest														17
Estimated amounts capitalized under the current accounting guidance						$ 130	$ 75