Consolidated Statements of Earnings - USD ($) shares in Thousands, $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues:
Net premiums, principally supplemental health insurance		$ 18,677	$ 18,531	$ 19,225
Net investment income		3,442	3,220	3,278
Realized investment gains (losses):
Other-than-temporary impairment losses realized		(81)
Other-than-temporary impairment losses realized			(37)	(85)
Other gains (losses)	[1]	(349)	(114)	71
Total realized investment gains (losses)		(430)	(151)	(14)
Other income (loss)		69	67	70
Total revenues		21,758	21,667	22,559
Benefits and expenses:
Benefits and claims, net		12,000	12,181	12,919
Acquisition and operating expenses:
Amortization of deferred policy acquisition costs		1,245	1,132	1,141
Insurance commissions		1,320	1,316	1,368
Insurance and other expenses	[2]	2,988	2,780	2,796
Interest expense		222	240	268
Total acquisition and operating expenses		5,775	5,468	5,573
Total benefits and expenses		17,775	17,649	18,492
Earnings before income taxes		3,983	4,018	4,067
Income Tax Expense:
Current		1,379	631	884
Deferred		(316)	(1,217)	524
Total income tax expense		1,063	(586)	1,408
Net earnings		$ 2,920	$ 4,604	$ 2,659
Net earnings per share:
Basic (in dollars per share)		$ 3.79	$ 5.81	$ 3.23
Diluted (in dollars per share)		$ 3.77	$ 5.77	$ 3.21
Weighted-average outstanding common shares used in computing earnings per share (In thousands):
Basic (in shares)		769,588	792,042	822,942
Diluted (in shares)		774,650	797,861	827,841
5.50% subordinated notes due September 2052
Expense on extinguishment of debt			$ 13
Senior Notes due 2039 and 2040
Expense on extinguishment of debt				$ 137

[1] See Note 1 of the Notes to the Consolidated Financial Statements for the adoption of accounting guidance on January 1, 2018 related to financial instruments.

[2] Includes expense of $13 in 2017 and $137 in 2016 for the early extinguishment of debt