Consolidated Statements Of Changes In Equity - USD ($) $ in Thousands	Total	Common Shares $1 Par Value [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Subtotal [Member]	Noncontrolling Interest [Member]
Beginning Balance at Dec. 31, 2014	$ 10,370,022	$ 367,499	$ 5,059,508	$ 447,082	$ 4,428,069	$ 10,302,158	$ 67,864
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	222,164				223,992	223,992	(1,828)
Other comprehensive loss, net of taxes	(31,227)			(31,227)		(31,227)
Contributions from noncontrolling interests	1,871					0	1,871
Deconsolidation of asset management entities	(8,193)					0	(8,193)
Change in interest in consolidated subsidiary	0		(862)			(862)	862
Share-based compensation expense	71,852		71,852			71,852
Change in fair value of redeemable noncontrolling interests	(8,306)		(8,306)			(8,306)
Exercise of options to purchase common shares, including excess tax benefit	44	2	42			44
Purchase of common shares for treasury	(121,619)	(5,713)	(115,906)			(121,619)
Dividends ($.1875 per common share)	(71,230)				(71,230)	(71,230)
Other	674	498	176			674
Ending Balance at Sep. 30, 2015	10,426,052	362,286	5,006,504	415,855	4,580,831	10,365,476	60,576
Beginning Balance at Dec. 31, 2015	10,465,890	362,617	4,986,819	438,793	4,612,982	10,401,211	64,679
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	(14,915)				(11,233)	(11,233)	(3,682)
Other comprehensive loss, net of taxes	(78,112)			(78,112)		(78,112)
Contributions from noncontrolling interests	118,940					0	118,940
Distributions to noncontrolling interests	(2,044)					0	(2,044)
Deconsolidation of asset management entities	(385)					0	(385)
Change in interest in consolidated subsidiary	0		(282)			(282)	282
Share-based compensation expense	24,936		24,936			24,936
Change in fair value of redeemable noncontrolling interests	(132,831)		(132,831)			(132,831)
Purchase of common shares for treasury	(73,124)	(4,300)	(68,824)			(73,124)
Dividends ($.1875 per common share)	(70,420)				(70,420)	(70,420)
Other	(458)	1,354	(1,829)			(475)	17
Ending Balance at Sep. 30, 2016	$ 10,237,477	$ 359,671	$ 4,807,989	$ 360,681	$ 4,531,329	$ 10,059,670	$ 177,807