Consolidated Statements of Equity (Unaudited) - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Capital in Excess of Par Value	Treasury Stock	Cumulative Net Income	Cumulative Dividends	Accumulated Other Comprehensive Income (Loss)	Other Equity	Noncontrolling Interests
Balances at beginning of period at Dec. 31, 2015	$ 15,175,885	$ 1,006,250	$ 354,811	$ 16,478,300	$ (44,372)	$ 3,725,772	$ (6,846,056)	$ (88,243)	$ 4,098	$ 585,325
Comprehensive income:
Net income (loss)	166,403					165,321				1,082
Other comprehensive income	(5,692)							(20,810)		15,118
Total comprehensive income	160,711
Decrease in noncontrolling interests	(127,042)			(5,717)						(121,325)
Amounts related to stock incentive plans, net of forfeitures	19,178		637	25,555	(6,899)				(115)
Proceeds from issuance of common stock	93,105		1,505	91,600
Option compensation expense	79								79
Cash dividends paid:
Common stock	(305,770)						(305,770)
Preferred Stock	(16,352)						(16,352)
Balances at end of period at Mar. 31, 2016	14,999,794	1,006,250	356,953	16,589,738	(51,271)	3,891,093	(7,168,178)	(109,053)	4,062	480,200
Balances at beginning of period at Dec. 31, 2016	15,281,472	1,006,250	363,071	16,999,691	(54,741)	4,803,575	(8,144,981)	(169,531)	3,059	475,079
Comprehensive income:
Net income (loss)	338,567					336,787				1,780
Other comprehensive income	(4,856)							(7,669)		2,813
Total comprehensive income	333,711
Increase in noncontrolling interests				932
Decrease in noncontrolling interests	(4,680)									(5,612)
Amounts related to stock incentive plans, net of forfeitures	(1,931)		336	6,903	(7,565)				(1,605)
Proceeds from issuance of common stock	118,984		1,780	117,204
Redemption of preferred stock	(287,509)	(287,500)		9,760		(9,769)
Option compensation expense	10								10
Cash dividends paid:
Common stock	(315,415)						(315,415)
Preferred Stock	(14,379)						(14,379)
Balances at end of period at Mar. 31, 2017	$ 15,110,263	$ 718,750	$ 365,187	$ 17,134,490	$ (62,306)	$ 5,130,593	$ (8,474,775)	$ (177,200)	$ 1,464	$ 474,060