Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Revenues
Net earned premiums	$ 1,649	$ 1,615
Net investment income	648	620
Net realized investment gains (losses), net of participating policyholders’ interests:
Other-than-temporary impairment losses	(15)	(20)
Portion of other-than-temporary impairments recognized in Other comprehensive income (loss)	(12)	(21)
Net other-than-temporary impairment losses recognized in earnings	(27)	(41)
Other net realized investment gains (losses)	63	54
Net realized investment gains (losses), net of participating policyholders’ interests	36	13
Other revenues	68	67
Total revenues	2,401	2,315
Claims, Benefits and Expenses
Insurance claims and policyholders’ benefits	1,381	1,364
Amortization of deferred acquisition costs	295	297
Other operating expenses	319	277
Interest	42	46
Total claims, benefits and expenses	2,037	1,984
Income (loss) from continuing operations before income tax	364	331
Income tax (expense) benefit	(114)	(101)
Income (loss) from continuing operations, net of tax	250	230
Income (loss) from discontinued operations, net of income tax (expense) benefit of - and $0		(1)
Net income (loss)	250	229
Net (income) loss attributable to noncontrolling interests		(9)
Net income (loss) attributable to CNA	250	220
Income (Loss) Attributable to Common Stockholders
Income (loss) from continuing operations attributable to CNA common stockholders	250	221
Income (loss) from discontinued operations attributable to CNA common stockholders		(1)
Income (loss) attributable to CNA common stockholders	$ 250	$ 220
Basic and Diluted Earnings (Loss) Per Share Attributable to CNA Common Stockholders
Income (loss) from continuing operations attributable to CNA common stockholders	$ 0.93	$ 0.82
Income (loss) from discontinued operations attributable to CNA common stockholders
Basic and diluted earnings (loss) per share attributable to CNA common stockholders	$ 0.93	$ 0.82
Dividends per share	$ 0.15	$ 0.10
Weighted Average Outstanding Common Stock and Common Stock Equivalents
Basic	269.3	269.2
Diluted	269.7	269.5