Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]	Total Parent Equity [Member]	Non-Controlling Interest in Subsidiaries [Member]
Beginning balance at Dec. 31, 2013	$ 3,358,768	$ 153,773	$ 14,935	$ (397,655)	$ 3,578,021	$ 3,349,074	$ 9,694
Beginning balance (in shares) at Dec. 31, 2013		153,773,098
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	711,286				711,286	711,286
Other comprehensive (loss) income, net of tax	(322,556)			(322,556)		(322,556)
Cash dividends declared	(352,564)				(352,564)	(352,564)
Stock options exercised, including tax benefit	(4,285)	$ 475	(4,760)			(4,285)
Stock options exercised, including tax benefit (in shares)		474,800
Share-based compensation	16,239		16,239			16,239
Purchase of stock	(95,946)	$ (1,135)			(94,811)	(95,946)
Purchase of stock (in shares)		(1,134,856)
Noncontrolling interest activities	1,422						1,422
Ending balance at Dec. 31, 2014	3,312,364	$ 153,113	26,414	(720,211)	3,841,932	3,301,248	11,116
Ending balance (in shares) at Dec. 31, 2014		153,113,042
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	705,672				705,672	705,672
Other comprehensive (loss) income, net of tax	(210,407)			(210,407)		(210,407)
Cash dividends declared	(372,840)				(372,840)	(372,840)
Stock options exercised, including tax benefit	(2,548)	$ 230	(2,778)			(2,548)
Stock options exercised, including tax benefit (in shares)		229,958
Share-based compensation	17,717		17,717			17,717
Purchase of stock	(292,275)	$ (3,262)			(289,013)	(292,275)
Purchase of stock (in shares)		(3,261,526)
Noncontrolling interest activities	1,559						1,559
Ending balance at Dec. 31, 2015	3,159,242	$ 150,081	41,353	(930,618)	3,885,751	3,146,567	12,675
Ending balance (in shares) at Dec. 31, 2015		150,081,474
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	687,240				687,240	687,240
Other comprehensive (loss) income, net of tax	(82,403)			(82,403)		(82,403)
Cash dividends declared	(391,852)				(391,852)	(391,852)
Stock options exercised, including tax benefit	$ (4,126)	$ 341	(4,467)			(4,126)
Stock options exercised, including tax benefit (in shares)	1,045,000	340,703
Share-based compensation	$ 19,719		19,719			19,719
Purchase of stock	(181,417)	$ (2,012)			(179,405)	(181,417)
Purchase of stock (in shares)		(2,011,755)
Noncontrolling interest activities	953						953
Ending balance at Dec. 31, 2016	$ 3,207,356	$ 148,410	$ 56,605	$ (1,013,021)	$ 4,001,734	$ 3,193,728	$ 13,628
Ending balance (in shares) at Dec. 31, 2016		148,410,422