Debt - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Operating Lease, Expense	$ 7,942,000	$ 8,387,000	$ 15,853,000	$ 15,947,000
Finance Lease, Right-of-Use Asset, Amortization	281,000	21,000	547,000	21,000
Finance Lease, Interest Expense	51,000	5,000	100,000	5,000
Short-term Lease Payments	6,185,000	5,640,000	12,611,000	11,245,000
Stockholders' Equity Attributable to Parent	2,612,412,000	2,119,439,000	2,612,412,000	2,119,439,000	$ 2,416,919,000	$ 2,341,244,000	$ 1,898,776,000	$ 1,808,562,000
Net income	164,075,000	210,209,000	339,778,000	398,615,000
Treasury Stock, Value, Acquired, Cost Method		(87,980,000)	(216,582,000)	(304,479,000)
APIC, Share-based Payment Arrangement, Increase for Cost Recognition		18,577,000	21,926,000	37,910,000
APIC, Share-based Payment Arrangement, Recognition and Exercise	16,984,000	79,857,000	126,046,000	178,831,000
Stock Issued During Period, Value, Stock Options Exercised	0	0	0	0
Lease, Cost	14,459,000	14,053,000	29,111,000	27,218,000
Operating cash flows from operating leases	6,676,000	6,314,000	13,394,000	12,877,000
Operating cash flows from finance leases	51,000	5,000	100,000	5,000
Financing cash flows from finance leases	212,000	12,000	412,000	12,000
Operating leases	1,901,000	3,571,000	5,685,000	9,551,000
Finance leases	0	4,692,000	440,000	5,227,000
Deferred Compensation Activity Adjustments	0		0	0
Common Stock [Member]
Debt Instrument [Line Items]
Stockholders' Equity Attributable to Parent	206,000	206,000	206,000	206,000	206,000	206,000	206,000	206,000
Additional Paid-In-Capital [Member]
Debt Instrument [Line Items]
Stockholders' Equity Attributable to Parent	2,151,623,000	1,962,156,000	2,151,623,000	1,962,156,000	2,127,315,000	2,055,407,000	1,899,100,000	1,820,223,000
APIC, Share-based Payment Arrangement, Increase for Cost Recognition		18,577,000	21,926,000	37,910,000
APIC, Share-based Payment Arrangement, Recognition and Exercise	16,984,000	79,857,000	126,046,000	178,831,000
Stock Issued During Period, Value, Stock Options Exercised	(7,110,000)	(35,378,000)	(51,756,000)	(74,808,000)
Retained Earnings [Member]
Debt Instrument [Line Items]
Stockholders' Equity Attributable to Parent	8,249,650,000	7,429,948,000	8,249,650,000	7,429,948,000	8,085,575,000	7,909,872,000	7,219,739,000	7,031,333,000
Net income	164,075,000	210,209,000	339,778,000	398,615,000
Treasury Stock [Member]
Debt Instrument [Line Items]
Stockholders' Equity Attributable to Parent	(7,789,067,000)	(7,272,871,000)	(7,789,067,000)	(7,272,871,000)	(7,796,177,000)	(7,624,241,000)	(7,220,269,000)	(7,043,200,000)
Treasury Stock, Value, Acquired, Cost Method		(87,980,000)	(216,582,000)	(304,479,000)
Stock Issued During Period, Value, Stock Options Exercised	7,110,000	35,378,000	51,756,000	74,808,000
Deferred Compensation Trust [Member]
Debt Instrument [Line Items]
Stockholders' Equity Attributable to Parent	(16,710,000)	(16,912,000)	(16,710,000)	(16,912,000)	(16,912,000)	(16,912,000)	(16,912,000)	(16,937,000)
Deferred Compensation Activity Adjustments	202,000		202,000	25,000
Deferred Compensation Liability [Member]
Debt Instrument [Line Items]
Stockholders' Equity Attributable to Parent	16,710,000	$ 16,912,000	16,710,000	16,912,000	$ 16,912,000	$ 16,912,000	$ 16,912,000	$ 16,937,000
Deferred Compensation Activity Adjustments	(202,000)		(202,000)	$ (25,000)
Senior Notes due 2022 [Member]
Debt Instrument [Line Items]
Senior notes principal amount	$ 600,000,000		$ 600,000,000
Senior notes interest rate	3.95%		3.95%
Frequency of senior notes payment			semi-annually in arrears on March 15 and September 15
Senior notes effective interest rate	3.97%		3.97%
Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum loan borrowing capacity	$ 200,000,000		$ 200,000,000
Increase in commitment available			300,000,000
Debt outstanding	0		0
Credit Agreement [Member] | Revolving Credit Facility [Member] | Sublimit for Issuance of Letters of Credit [Member]
Debt Instrument [Line Items]
Maximum loan borrowing capacity	100,000,000		100,000,000
Letters of credit outstanding	11,200,000		11,200,000
Credit Agreement [Member] | Revolving Credit Facility [Member] | Sublimit for Swing Line Commitment [Member]
Debt Instrument [Line Items]
Maximum loan borrowing capacity	25,000,000		25,000,000
Repurchase Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum loan borrowing capacity	150,000,000		150,000,000
Debt outstanding	0		0
Senior Notes Due Two Thousand Thirty [Member]
Debt Instrument [Line Items]
Senior notes principal amount	$ 600,000,000		$ 600,000,000
Senior notes interest rate	3.00%		3.00%
Frequency of senior notes payment			semi-annually in arrears on May 15 and November 15
Senior notes effective interest rate	3.02%		3.02%
Proceeds from Debt, Net of Issuance Costs			$ 595,300,000
Proceeds from Debt, Net of Issuance Costs			$ 595,300,000