Consolidated Condensed Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Amounts Reclassified Out Of Accumulated Other Comprehensive Income Loss [Abstract]
Net income (loss)	$ 393	$ 282	$ 304	$ 578
Other comprehensive income (loss), after tax Changes in:
Net unrealized gains (losses) on investments with other-than-temporary impairments	3	2	7	(3)
Net other unrealized gains (losses) on investments	42	(39)	591	(292)
Total unrealized gains (losses) on available-for-sale investments	45	(37)	598	(295)
Unrealized gains on cash flow hedges	1	1	2	5
Pension liability	7	4	20	51
Foreign currency	(24)	(53)	(58)	(100)
Other comprehensive income (loss)	29	(85)	562	(339)
Comprehensive income	422	197	866	239
Amounts attributable to noncontrolling interests	(70)	(91)	(1)	(82)
Total comprehensive income attributable to Loews Corporation	$ 352	$ 106	$ 865	$ 157

Amounts Reclassified Out Of Accumulated Other Comprehensive Income Loss [Abstract]

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Unrealized Gains Losses On Available For Sale Investments

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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