Consolidated Statements of Earnings (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Revenues:
Premiums, principally supplemental health insurance	$ 22,148		$ 20,362		$ 18,073
Net investment income	3,473		3,280		3,007
Realized investment gains (losses):
Other-than-temporary impairment losses realized	(977)	[1]	(1,901)	[1]	(459)	[2]
Sales and redemptions	474		594		38
Derivative and other gains (losses)	154		(245)		(1)
Total realized investment gains (losses)	(349)		(1,552)		(422)
Other income	92		81		74
Total revenues	25,364		22,171		20,732
Benefits and expenses:
Benefits and claims	15,330		13,749		12,106
Acquisition and operating expenses:
Amortization of deferred policy acquisition costs	1,117		1,033		958
Insurance commissions	1,744		1,725		1,637
Insurance expenses	2,415		2,336		2,159
Interest expense	261		196		149
Other operating expenses	195		182		162
Total acquisition and operating expenses	5,732		5,472		5,065
Total benefits and expenses	21,062		19,221		17,171
Earnings before income taxes	4,302		2,950		3,561
Income Tax Expense:
Current	816		891		862
Deferred	620		122		371
Total income tax expense	1,436		1,013		1,233
Net earnings	$ 2,866		$ 1,937		$ 2,328
Net earnings per share:
Basic (in dollars per share)	$ 6.14		$ 4.16		$ 4.96
Diluted (in dollars per share)	$ 6.11		$ 4.12		$ 4.92
Weighted-average outstanding common shares used in computing earnings per share (In thousands):
Basic (in shares)	466,868		466,519		469,038
Diluted (in shares)	469,287		469,370		473,085

[1] Includes $597 and $1,286 for the years ended December 31, 2012 and 2011, respectively, for credit-related impairments; $353 and $615 for the years ended December 31, 2012 and 2011, respectively, from change in intent to sell securities; and $27 for the year ended December 31, 2012 for impairments due to severity and duration of decline in fair value

[2] Consisted completely of credit-related impairments