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, 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 ($0.48 per share for three and six month June 30 2019 and $0.44 per share for three and six month June 30 2018)	(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 inbusiness 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	4,679,830	$ 628	3,381,280	(127,485)	1,422,207	4,676,630	3,200
Beginning Balance (in shares) at Mar. 31, 2018		62,948
Consolidated net earnings	185,503				185,377	185,377	126
Other comprehensive earnings, net of tax	1,603			1,602		1,602	1
Dividends declared ($0.48 per share for three and six month June 30 2019 and $0.44 per share for three and six month June 30 2018)	(27,910)				(27,910)	(27,910)
Issuances of common stock for stock award plans	4,096	$ 1	4,095			4,096
Issuances of common stock for stock award plans (in shares)		64
Shares withheld for employees' income tax obligations	(3,685)		(3,685)			(3,685)
Stock-based compensation expense	7,338		7,338			7,338
Noncontrolling interest acquired inbusiness combination	8,695						8,695
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 Dec. 31, 2018	4,949,412	$ 624	3,396,059	(143,579)	1,693,259	4,946,363	3,049
Beginning Balance (in shares) at Dec. 31, 2018		62,515
Consolidated net earnings	232,296				232,328	232,328	(32)
Other comprehensive earnings, net of tax	6,245			6,245		6,245
Dividends declared ($0.48 per share for three and six month June 30 2019 and $0.44 per share for three and six month June 30 2018)	(60,615)				(60,615)	(60,615)
Issuances of common stock for stock award plans	10,456	$ 1	10,455			10,456
Issuances of common stock for stock award plans (in shares)		150
Shares withheld for employees' income tax obligations	(12,174)		(12,174)			(12,174)
Repurchases of common stock	(50,000)	$ (2)			(49,998)	(50,000)
Repurchases of common stock, Shares		(232)
Stock-based compensation expense	22,250		22,250			22,250
Distributions to owners of noncontrolling interest	(600)						(600)
Ending Balance at Jun. 30, 2019	5,097,270	$ 623	3,416,590	(137,334)	1,814,974	5,094,853	2,417
Ending Balance (in shares) at Jun. 30, 2019		62,433
Beginning Balance at Mar. 31, 2019	4,975,496	$ 625	3,406,456	(140,324)	1,705,717	4,972,474	3,022
Beginning Balance (in shares) at Mar. 31, 2019		62,593
Consolidated net earnings	189,469				189,475	189,475	(6)
Other comprehensive earnings, net of tax	2,991			2,990		2,990	1
Dividends declared ($0.48 per share for three and six month June 30 2019 and $0.44 per share for three and six month June 30 2018)	(30,220)				(30,220)	(30,220)
Issuances of common stock for stock award plans	6,482		6,482			6,482
Issuances of common stock for stock award plans (in shares)		72
Shares withheld for employees' income tax obligations	(5,046)		(5,046)			(5,046)
Repurchases of common stock	(50,000)	$ (2)			(49,998)	(50,000)
Repurchases of common stock, Shares		(232)
Stock-based compensation expense	8,698		8,698			8,698
Distributions to owners of noncontrolling interest	(600)						(600)
Ending Balance at Jun. 30, 2019	$ 5,097,270	$ 623	$ 3,416,590	$ (137,334)	$ 1,814,974	$ 5,094,853	$ 2,417
Ending Balance (in shares) at Jun. 30, 2019		62,433