CONSOLIDATED CONDENSED STATEMENTS OF EQUITY - 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, Adjustment [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Retained Earnings [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]
Balance at Dec. 31, 2019	$ 21,930	$ 3	$ 3,374	$ 15,823	$ (68)	$ (13)	$ 2,811	$ (5)	$ (5)	$ 21,925	$ 3	$ 3,374	$ 15,818	$ (68)	$ (13)	$ 2,811
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	(1,890)			(1,467)			(423)
Other comprehensive income (loss)	84				73		11
Dividends paid per share	(114)			(36)
Dividends paid per share							(78)
Deconsolidation of Diamond Offshore	(1,087)						(1,087)
Purchases of Loews Corporation treasury stock	(478)					(478)
Purchases of subsidiary stock from non-controlling 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 (loss)	1,228				1,098		130
Dividends paid per share	(27)			(18)
Dividends paid per share							(9)
Deconsolidation of Diamond Offshore	(1,087)						(1,087)
Purchases of Loews Corporation treasury stock	(33)					(33)
Purchases of subsidiary stock from non-controlling 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
Balance at Dec. 31, 2020	19,181	3	3,133	14,150	581	(7)	1,321
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	1,086			1,015			71
Other comprehensive income (loss)	(285)				(254)		(31)
Dividends paid per share	(76)			(33)
Dividends paid per share							(43)
Purchases of Loews Corporation treasury stock	(493)					(493)
Purchases of subsidiary stock from non-controlling interests	(18)						(18)
Stock-based compensation	7		(9)				16
Other	(4)		(3)				(1)
Balance at Jun. 30, 2021	19,398	3	3,121	15,132	327	(500)	1,315
Balance at Mar. 31, 2021	18,537	3	3,119	14,394	34	(280)	1,267
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	793			754			39
Other comprehensive income (loss)	326				293		33
Dividends paid per share	(27)			(16)
Dividends paid per share							(11)
Purchases of Loews Corporation treasury stock	(219)					(219)
Purchases of subsidiary stock from non-controlling interests	(15)						(15)
Stock-based compensation	3		2				1
Other	0					(1)	1
Balance at Jun. 30, 2021	$ 19,398	$ 3	$ 3,121	$ 15,132	$ 327	$ (500)	$ 1,315