Consolidated Statements of Total Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Retained Earnings	Total Shareholders' Equity	Noncontrolling Interests
Beginning Balance at Dec. 31, 2016	$ 4,142,590	$ 630	$ 3,334,461	$ (130,687)	$ 935,574	$ 4,139,978	$ 2,612
Beginning Balance (in shares) at Dec. 31, 2016		63,176
Consolidated net earnings	184,548				184,613	184,613	(65)
Other comprehensive earnings, net of tax	4,783			4,781		4,781	2
Dividends declared	(53,135)				(53,135)	(53,135)
Issuances of common stock for stock award plans	12,744	$ 2	12,742			12,744
Issuances of common stock for stock award plans (in shares)		122
Shares withheld for employees' income tax obligations	(8,938)		(8,938)			(8,938)
Repurchases of common stock	(99,999)	$ (5)			(99,994)	(99,999)
Repurchases of common stock, (in shares)		(458)
Stock-based compensation expense	17,727		17,727			17,727
Contributions by owners of noncontrolling interest	211						211
Ending Balance at Jun. 30, 2017	4,200,531	$ 627	3,355,992	(125,906)	967,058	4,197,771	2,760
Ending Balance (in shares) at Jun. 30, 2017		62,840
Beginning Balance at Mar. 31, 2017				(128,425)
Consolidated net earnings	142,241
Ending Balance at Jun. 30, 2017	4,200,531	$ 627	3,355,992	(125,906)	967,058	4,197,771	2,760
Ending Balance (in shares) at Jun. 30, 2017		62,840
Beginning Balance at Dec. 31, 2017	4,682,477	$ 628	3,368,007	(129,104)	1,440,069	4,679,600	2,877
Beginning Balance (in shares) at Dec. 31, 2017		62,873
Consolidated net earnings	195,543				195,400	195,400	143
Other comprehensive earnings, net of tax	3,222			3,221		3,221	1
Dividends declared	(55,795)				(55,795)	(55,795)
Issuances of common stock for stock award plans	13,989	$ 1	13,988			13,989
Issuances of common stock for stock award plans (in shares)		139
Shares withheld for employees' income tax obligations	(10,065)		(10,065)			(10,065)
Stock-based compensation expense	17,098		17,098			17,098
Noncontrolling interest acquired in business combination	9,001						9,001
Ending Balance at Jun. 30, 2018	4,855,470	$ 629	3,389,028	(125,883)	1,579,674	4,843,448	12,022
Ending Balance (in shares) at Jun. 30, 2018		63,012
Beginning Balance at Mar. 31, 2018				(127,485)
Consolidated net earnings	185,503
Ending Balance at Jun. 30, 2018	$ 4,855,470	$ 629	$ 3,389,028	$ (125,883)	$ 1,579,674	$ 4,843,448	$ 12,022
Ending Balance (in shares) at Jun. 30, 2018		63,012