Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Amounts Reclassified Out Of Accumulated Other Comprehensive Income Loss [Abstract]
Net income	$ 287	$ 962	$ 1,069
Other comprehensive income (loss), after tax Changes in:
Net unrealized gains (losses) on investments with other- than-temporary impairments	(9)	15	6
Net other unrealized gains (losses) on investments	(557)	267	(679)
Total unrealized gains (losses) on available-for-sale investments	(566)	282	(673)
Discontinued operations		(19)	(23)
Unrealized gains (losses) on cash flow hedges	5	(3)
Pension liability	(18)	(235)	329
Foreign currency translation	(139)	(94)	(11)
Other comprehensive loss	(718)	(69)	(378)
Comprehensive income (loss)	(431)	893	691
Amounts attributable to noncontrolling interests	53	(361)	(437)
Total comprehensive income (loss) attributable to Loews Corporation	$ (378)	$ 532	$ 254

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

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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 of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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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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Amount after tax of other than temporary impairment (OTTI) loss on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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