Selected Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2017

Quarterly Financial Information Disclosure [Abstract]

Schedule of Selected Quarterly Financial Data

Fiscal Quarters Year Ended December 31, 2017	First		Second		Third		Fourth
Revenues, net	$	520,433	$	541,237	$	577,877	$	609,991
Operating income	195,068		216,043		232,637		240,012
Net income	123,693		130,987		202,823		282,697
Basic earnings per share	$	1.34	$	1.42	$	2.23	$	3.15
Diluted earnings per share	1.31		1.39		2.18		3.05
Weighted average shares outstanding:
Basic shares	92,108		92,013		90,751		89,676
Diluted shares	94,560		94,223		93,001		92,623

Fiscal Quarters Year Ended December 31, 2016*	First		Second		Third		Fourth
Revenues, net	$	414,262	$	417,905	$	484,426	$	514,953
Operating income	175,955		171,168		191,055		215,975
Net income	111,090		116,253		129,618		95,424
Earnings per share:
Basic earnings per share	$	1.20	$	1.25	$	1.40	$	1.03
Diluted earnings per share	1.17		1.22		1.36		1.00
Weighted average shares outstanding:
Basic shares	92,516		92,665		92,631		92,574
Diluted shares	95,030		95,279		95,307		95,235

*2016 quarterly amounts reflect the impact of the Company's adoption of Accounting Standards Update 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payments Accounting, to simplify several aspects of the accounting for share-based compensation, including the income tax consequences.