Summarize Impact of ASC 606 to Condensed Consolidated Statement of Operation (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	$ 566,848	$ 503,378	$ 1,581,244	$ 1,657,191
Total cost of revenues	233,155		670,385
Income tax provision	20,863	24,017	48,684	62,713
Net income	$ 119,981	$ 103,420	$ 307,991	$ 363,616
Net income per common share:
Basic	$ 0.65	$ 0.52	$ 1.62	$ 1.83
Diluted	$ 0.63	$ 0.52	$ 1.57	$ 1.81
ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	$ 564,500		$ 1,571,000
ASU 2014-09 | Adjustments to Recognize Under Legacy GAAP
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	59,738		(32,668)
Total cost of revenues	21,702		(11,708)
Income tax provision	4,771		(4,163)
Net income	$ 33,265		$ (16,797)
Net income per common share:
Basic	$ 0.18		$ (0.09)
Diluted	$ 0.17		$ (0.09)
ASU 2014-09 | Legacy GAAP
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	$ 626,586		$ 1,548,576
Total cost of revenues	254,857		658,677
Income tax provision	25,634		44,521
Net income	$ 153,246		$ 291,194
Net income per common share:
Basic	$ 0.83		$ 1.53
Diluted	$ 0.80		$ 1.48