Consolidated Statements of Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)	Total shareholders' equity	Noncontrolling interest
Balance at Dec. 31, 2009	$ 1,561,347	$ 2,120	$ 18,265	$ 1,532,018	$ 604	$ 1,553,007	$ 8,340
Balance (in shares) at Dec. 31, 2009		212,025,494
Increase (Decrease) in Equity [Roll Forward]
Exercise of stock options and release of restricted shares (in shares)		4,781,971
Exercise of stock options and release of restricted shares	79,234	48	79,186	0	0	79,234
Issuance of shares under stock purchase plan (in shares)		694,329
Issuance of shares under stock purchase plan	20,550	7	20,543	0	0	20,550
Shares repurchased under provisions of stock repurchase plans (in shares)		(5,454,020)
Shares repurchased under provisions of stock repurchase plans	(246,312)	(55)	(172,188)	(74,069)	0	(246,312)
Stock compensation expense	43,743		43,743	0	0	43,743
Tax benefits from stock plans, net	23,863		23,863	0	0	23,863
Net earnings	344,205			344,172		344,172	33
Other comprehensive income (loss)	7,447				7,521	7,521	(74)
Dividends paid	(84,872)			(84,872)		(84,872)
Distributions of dividends to noncontrolling interest	(1,051)						(1,051)
Balance at Dec. 31, 2010	1,748,154	2,120	13,412	1,717,249	8,125	1,740,906	7,248
Balance (in shares) at Dec. 31, 2010		212,047,774
Increase (Decrease) in Equity [Roll Forward]
Exercise of stock options and release of restricted shares (in shares)		1,632,077
Exercise of stock options and release of restricted shares	32,422	16	32,406	0	0	32,422
Issuance of shares under stock purchase plan (in shares)		663,386
Issuance of shares under stock purchase plan	24,224	7	24,217	0	0	24,224
Shares repurchased under provisions of stock repurchase plans (in shares)		(2,339,575)
Shares repurchased under provisions of stock repurchase plans	(112,071)	(23)	(106,353)	(5,695)	0	(112,071)
Stock compensation expense	44,278		44,278	0	0	44,278
Tax benefits from stock plans, net	5,300		5,300	0	0	5,300
Net earnings	386,243			385,679		385,679	564
Other comprehensive income (loss)	(11,515)				(11,089)	(11,089)	(426)
Dividends paid	(106,011)			(106,011)		(106,011)
Distributions of dividends to noncontrolling interest	(955)						(955)
Balance at Dec. 31, 2011	2,010,069	2,120	13,260	1,991,222	(2,964)	2,003,638	6,431
Balance (in shares) at Dec. 31, 2011	212,003,662	212,003,662
Increase (Decrease) in Equity [Roll Forward]
Exercise of stock options and release of restricted shares (in shares)		1,653,994
Exercise of stock options and release of restricted shares	29,119	16	29,103	0	0	29,119
Issuance of shares under stock purchase plan (in shares)		773,661
Issuance of shares under stock purchase plan	23,392	8	23,384	0	0	23,392
Shares repurchased under provisions of stock repurchase plans (in shares)		(8,039,304)
Shares repurchased under provisions of stock repurchase plans	(302,414)	(80)	(113,633)	(188,701)	0	(302,414)
Stock compensation expense	44,058		44,058	0	0	44,058
Tax benefits from stock plans, net	5,111		5,111	0	0	5,111
Net earnings	332,969			333,360		333,360	(391)
Other comprehensive income (loss)	8,811				8,698	8,698	113
Dividends paid	(117,263)			(117,263)		(117,263)
Distributions of dividends to noncontrolling interest	(1,282)						(1,282)
Balance at Dec. 31, 2012	$ 2,032,570	$ 2,064	$ 1,283	$ 2,018,618	$ 5,734	$ 2,027,699	$ 4,871
Balance (in shares) at Dec. 31, 2012	206,392,013	206,392,013