Consolidated Statement of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Treasury Stock	Capital in Excess of Par Value	Accumulated Deficit(1)	Accumulated Other Comprehensive Income	Noncontrolling Interest
Balance at beginning of period at Dec. 31, 2015	$ 1,189,401	$ 200,859	$ (5,086)	$ 1,092,106	$ (109,351)	$ 6,164	$ 4,709
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Comprehensive income	187,636	0	0	0	177,038	10,328	270
Dividends declared on common stock	(98,418)	0	0	(98,418)	0	0	0
Stock option exercises	17,662	2,108	0	15,554	0	0	0
Restricted stock awards, net of forfeitures	0	241	(1)	(240)	0	0	0
Employee share-based compensation earned	14,056		0
Purchase of Company common stock	(227,928)	0		14,056	0	0	0
Tax benefits related to stock-based awards	12,685	0	0	12,685	0	0
Purchase of noncontrolling interest	(1,961)	0	(8,812)	(48,042)	(171,074)	0	0
Acquisition		0	0	364	0	0	(2,325)
Noncontrolling interest payments	$ (120)	$ 0	$ 0	$ 0	$ 0	$ 0	$ (120)
Retirement of treasury shares	0	(7,901)	(7,901)	0	0	0	0
Other	$ 2,234	$ 96	$ 0	$ 2,138	$ 0	$ 0	$ 0
Balance at end of period at Dec. 31, 2016	1,095,247	195,403	(5,998)	990,203	(103,387)	16,492	2,534
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Comprehensive income	572,309	0	0	0	546,663	25,451	195
Dividends declared on common stock	(108,750)	0	0	(37,011)	(71,739)	0	0
Stock option exercises	33,611	2,759	0	30,852	0	0	0
Restricted stock awards, net of forfeitures	0	209	(2)	(207)	0	0	0
Employee share-based compensation earned	14,788	0	0	14,788	0	0	0
Purchase of Company common stock	(199,637)	0	(6,211)	(32,253)	(161,173)	0	0
Purchase of noncontrolling interest	(4,580)	0	0	(2,258)	0	0	(2,322)
Noncontrolling interest payments	$ (360)	$ 0	$ 0	$ 0	$ 0	$ 0	$ (360)
Retirement of treasury shares	0	(6,890)	(6,890)	0	0	0	0
Other	$ 6,809	$ 455	$ 0	$ 6,354	$ 0	$ 0	$ 0
Balance at end of period at Dec. 31, 2017	1,409,437	191,936	(5,321)	970,468	210,364	41,943	47
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Comprehensive income	419,080	0	0	0	447,208	(28,319)	191
Dividends declared on common stock	(123,849)	0	0	0	(123,849)	0	0
Stock option exercises	24,517	1,802	0	22,715	0	0	0
Restricted stock awards, net of forfeitures	0	178	0	(178)	0	0	0
Employee share-based compensation earned	15,626	0	0	15,626	0	0	0
Purchase of Company common stock	(277,611)	0	(7,348)	(38,404)	(231,859)	0	0
Noncontrolling interest payments	$ (326)	$ 0	$ 0	$ 0	$ 0	$ 0	$ 326
Retirement of treasury shares	0	(9,419)	(9,419)	0	0	0	0
Other	$ 2,709	$ 224	$ 0	$ 2,483	$ 2	$ 0	$ 0
Balance at end of period at Dec. 31, 2018	1,641,815	184,721	(3,250)	972,710	474,327	13,395	(88)
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption	$ 172,232	$ 0	$ 0	$ 0	$ 172,461	$ (229)	$ 0