Consolidated Condensed Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Amounts Reclassified Out Of Accumulated Other Comprehensive Income Loss [Abstract]
Net income (loss)	$ (288)	$ 247	$ (89)	$ 296
Other comprehensive income (loss), after tax Changes in:
Net unrealized gains (losses) on investments with other-than-temporary impairments	(1)	(4)	4	(5)
Net other unrealized gains (losses) on investments	321	(363)	549	(253)
Total unrealized gains (losses) on available-for-sale investments	320	(367)	553	(258)
Unrealized gains on cash flow hedges		1	1	4
Pension liability	5	43	13	47
Foreign currency	(48)	49	(34)	(47)
Other comprehensive income (loss)	277	(274)	533	(254)
Comprehensive income (loss)	(11)	(27)	444	42
Amounts attributable to noncontrolling interests	191	(48)	69	9
Total comprehensive income (loss) attributable to Loews Corporation	$ 180	$ (75)	$ 513	$ 51

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 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 increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (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 and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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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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