Debt (Schedule Of Debt By Subsidiary) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Schedule Of Debt By Subsidiary [Line Items]
Principal	$ 9,046	$ 9,524
Unamortized Discount	45	47
Net	9,001	9,477
Short Term Debt	88	647
Long Term Debt	8,913	8,830
Loews Corp [Member]
Schedule Of Debt By Subsidiary [Line Items]
Principal	700
Unamortized Discount	6
Net	694
Short Term Debt		175
Long Term Debt	694	692
CNA Financial [Member]
Schedule Of Debt By Subsidiary [Line Items]
Principal	2,625
Unamortized Discount	17
Net	2,608
Short Term Debt	83
Long Term Debt	2,525
Diamond Offshore [Member]
Schedule Of Debt By Subsidiary [Line Items]
Principal	1,500
Unamortized Discount	12
Net	1,488
Long Term Debt	1,488
HighMount [Member]
Schedule Of Debt By Subsidiary [Line Items]
Principal	700
Net	700
Long Term Debt	700
Boardwalk Pipeline [Member]
Schedule Of Debt By Subsidiary [Line Items]
Principal	3,408
Unamortized Discount	10
Net	3,398
Long Term Debt	3,398
Loews Hotels [Member]
Schedule Of Debt By Subsidiary [Line Items]
Principal	213
Net	213
Short Term Debt	5
Long Term Debt	208
Elimination Of Intercompany Debt [Member]
Schedule Of Debt By Subsidiary [Line Items]
Principal	(100)	(100)
Net	(100)
Long Term Debt	$ (100)