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)	(1,728)			(1,328)			(400)
Other comprehensive income (loss)	343				306		37
Dividends paid per share	(141)			(53)
Dividends paid per share							(88)
Deconsolidation of Diamond Offshore	(1,087)						(1,087)
Purchases of Loews Corporation treasury stock	(673)					(673)
Purchases of subsidiary stock from non-controlling interests	(37)		5				(42)
Stock-based compensation	17		(1)				18
Other	1		1			1	(1)
Balance at Sep. 30, 2020	18,620	3	3,379	14,437	238	(685)	1,248
Balance at Jun. 30, 2020	18,413	3	3,371	14,316	5	(491)	1,209
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	162			139			23
Other comprehensive income (loss)	259				233		26
Dividends paid per share	(27)			(17)
Dividends paid per share							(10)
Purchases of Loews Corporation treasury stock	(195)					(195)
Stock-based compensation	8		8
Other	0			(1)		1
Balance at Sep. 30, 2020	18,620	3	3,379	14,437	238	(685)	1,248
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)	1,332			1,235			97
Other comprehensive income (loss)	(438)				(390)		(48)
Dividends paid per share	(103)			(49)
Dividends paid per share							(54)
Purchases of Loews Corporation treasury stock	(826)					(826)
Purchases of subsidiary stock from non-controlling interests	(18)						(18)
Stock-based compensation	5		(11)				16
Other	(3)		(2)				(1)
Balance at Sep. 30, 2021	19,130	3	3,120	15,336	191	(833)	1,313
Balance at Jun. 30, 2021	19,398	3	3,121	15,132	327	(500)	1,315
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	246			220			26
Other comprehensive income (loss)	(153)				(136)		(17)
Dividends paid per share	(27)			(16)
Dividends paid per share							(11)
Purchases of Loews Corporation treasury stock	(333)					(333)
Stock-based compensation	(2)		(2)
Other	1		1
Balance at Sep. 30, 2021	$ 19,130	$ 3	$ 3,120	$ 15,336	$ 191	$ (833)	$ 1,313