Consolidated Statement of Changes in Equity - USD ($) $ in Millions	Total	Total	Common Shares	Common Stock and Capital Surplus	Retained Earnings Approp.	Retained Earnings Unapprop.	Accumulated Other Comprehensive Inc. (Loss)	Noncontrolling Interests
Beginning Balance, shares at Dec. 31, 2013			89,513,386
Beginning Balance at Dec. 31, 2013	$ 4,769	$ 4,599		$ 1,213	$ 49	$ 2,777	$ 560	$ 170
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	406	452				452		(46)
Other comprehensive income (loss)	170	167					167	3
Allocation of losses of managed investment entities	0	(51)			(51)			51
Dividends on Common Stock	(169)	(169)				(169)
Shares issued:
Exercise of stock options, shares			1,262,313
Exercise of stock options	36	36		36
Restricted stock awards, shares			102,330
Restricted stock awards	0	0		0
Other benefit plans, shares			140,339
Other benefit plans	8	8		8
Dividend reinvestment plan, shares			27,238
Dividend reinvestment plan	2	2		2
Stock-based compensation:
Stock-based compensation: Expense	19	19		19
Stock-based compensation: Excess tax benefits	9	9		9
Shares acquired and retired, shares			(3,303,639)
Shares acquired and retired	(191)	(191)		(46)		(145)
Shares exchanged — benefit plans, shares			(33,174)
Shares exchanged — benefit plans	(2)	(2)		(1)		(1)
Other	(3)					0		(3)
Ending Balance, shares at Dec. 31, 2014			87,708,793
Ending Balance at Dec. 31, 2014	5,054	4,879		1,240	(2)	2,914	727	175
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting change	2	2			2
Net earnings	370	352				352		18
Other comprehensive income (loss)	(431)	(423)					(423)	(8)
Dividends on Common Stock	(178)	(178)				(178)
Shares issued:
Exercise of stock options, shares			1,475,202
Exercise of stock options	47	47		47
Restricted stock awards, shares			171,130
Restricted stock awards	0	0		0
Other benefit plans, shares			111,681
Other benefit plans	7	7		7
Dividend reinvestment plan, shares			26,167
Dividend reinvestment plan	2	2		2
Stock-based compensation:
Stock-based compensation: Expense	21	21		21
Stock-based compensation: Excess tax benefits	12	12		12
Shares acquired and retired, shares			(1,955,186)
Shares acquired and retired	(126)	(126)		(27)		(99)
Shares exchanged — benefit plans, shares			(45,765)
Shares exchanged — benefit plans	(3)	(3)		(1)		(2)
Forfeitures of restricted stock, shares			(17,570)
Forfeitures of restricted stock	0	0		0
Other	$ (7)	0				0	0	(7)
Ending Balance, shares at Dec. 31, 2015	87,474,452		87,474,452
Ending Balance at Dec. 31, 2015	$ 4,770	4,592		1,301	0	2,987	304	178
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	668	649				649		19
Other comprehensive income (loss)	67	62					62	5
Dividends on Common Stock	$ (187)	(187)				(187)
Shares issued:
Exercise of stock options, shares	958,344		958,344
Exercise of stock options	$ 32	32		32
Restricted stock awards, shares			318,940
Restricted stock awards	0	0		0
Other benefit plans, shares			95,875
Other benefit plans	7	7		7
Dividend reinvestment plan, shares			25,516
Dividend reinvestment plan	2	2		2
Stock-based compensation:
Stock-based compensation: Expense	22	22		22
Shares acquired and retired, shares			(1,911,976)
Shares acquired and retired	(133)	(133)		(29)		(104)
Shares exchanged — benefit plans, shares			(32,707)
Shares exchanged — benefit plans	(2)	(2)		0		(2)
Forfeitures of restricted stock, shares			(4,045)
Forfeitures of restricted stock	0	0		0
Acquisition of noncontrolling interests	(315)	(128)		(137)			9	(187)
Other	$ (12)							(12)
Ending Balance, shares at Dec. 31, 2016	86,924,399		86,924,399
Ending Balance at Dec. 31, 2016	$ 4,919	$ 4,916		$ 1,198	$ 0	$ 3,343	$ 375	$ 3