CONSOLIDATED CONDENSED STATEMENTS OF EQUITY (Unaudited) - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Common Stock Held in Treasury [Member]	Noncontrolling Interests [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Common Stock [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Additional Paid-in Capital [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Retained Earnings [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Accumulated Other Comprehensive Income (Loss) [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Common Stock Held in Treasury [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Noncontrolling Interests [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Retained Earnings [Member]
Balance at Dec. 31, 2018	$ 21,386	$ 3	$ 3,627	$ 15,773	$ (880)	$ (5)	$ 2,868
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	621			643			(22)
Other comprehensive income	989				883		106
Dividends paid	(116)			(38)
Dividends paid							(78)
Purchases of Loews Corporation treasury stock	(473)					(473)
Purchases of subsidiary stock from noncontrolling interests	(16)						(16)
Stock-based compensation	8		(13)				21
Other	(5)		(2)	(4)			1
Balance at Jun. 30, 2019	22,394	3	3,612	16,374	3	(478)	2,880
Balance at Mar. 31, 2019	21,902	3	3,607	16,144	(390)	(327)	2,865
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	225			249			(24)
Other comprehensive income	440				393		47
Dividends paid	(29)			(19)
Dividends paid							(10)
Purchases of Loews Corporation treasury stock	(151)					(151)
Purchases of subsidiary stock from noncontrolling interests	(2)						(2)
Stock-based compensation	7		6				1
Other	2		(1)				3
Balance at Jun. 30, 2019	22,394	3	3,612	16,374	3	(478)	2,880
Balance at Dec. 31, 2019	21,930	3	3,374	15,823	(68)	(13)	2,811	$ 21,925	$ 3	$ 3,374	$ 15,818	$ (68)	$ (13)	$ 2,811
Balance (ASU 2016-13 [Member]) at Dec. 31, 2019															$ (5)	$ (5)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	(1,890)			(1,467)			(423)
Other comprehensive income	84				73		11
Dividends paid	(114)			(36)
Dividends paid							(78)
Deconsolidation of Diamond Offshore	(1,087)						(1,087)
Purchases of Loews Corporation treasury stock	(478)					(478)
Purchases of subsidiary stock from noncontrolling interests	(37)		5				(42)
Stock-based compensation	9		(9)				18
Other	1		1	1			(1)
Balance at Jun. 30, 2020	18,413	3	3,371	14,316	5	(491)	1,209
Balance at Mar. 31, 2020	19,178	3	3,347	15,167	(1,093)	(458)	2,212
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	(846)			(835)			(11)
Other comprehensive income	1,228				1,098		130
Dividends paid	(27)			(18)
Dividends paid							(9)
Deconsolidation of Diamond Offshore	(1,087)						(1,087)
Purchases of Loews Corporation treasury stock	(33)					(33)
Purchases of subsidiary stock from noncontrolling interests	(19)		5				(24)
Stock-based compensation	13		13
Other	6		6	2			(2)
Balance at Jun. 30, 2020	$ 18,413	$ 3	$ 3,371	$ 14,316	$ 5	$ (491)	$ 1,209