CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss) Income	Accumulated Deficit
Balance at Dec. 31, 2017	$ 1,953,646	$ 24,444	$ 1,638,413	$ 18,776	$ 272,013
Balance, Shares at Dec. 31, 2017		195,548
Net issuance of common stock under stock-based plans	2,010	$ 197	1,813
Net issuance of common stock under stock-based plans (in shares)		1,584
Stock-based compensation expense	24,342		24,342
Repurchase of common stock	(568,660)	$ (1,730)			(566,930)
Repurchase of common stock (in shares)		(13,843)
Cash dividends	(51,352)				(51,352)
Net income	307,991				307,991
Other comprehensive loss	(12,896)			(12,896)
Reclassification of unrealized gains on equity securities				(3,125)	3,125
Reclassification of tax effects resulting from the Tax Reform Act				769	(769)
Balance at Sep. 30, 2018	1,667,760	$ 22,911	1,664,568	3,524	(23,243)
Balance, Shares at Sep. 30, 2018		183,289
Balance at Jul. 01, 2018	1,739,940	$ 23,495	1,645,679	(3,504)	74,270
Balance, Shares at Jul. 01, 2018		187,962
Net issuance of common stock under stock-based plans	10,098	$ 42	10,056
Net issuance of common stock under stock-based plans (in shares)		332
Stock-based compensation expense	8,833		8,833
Repurchase of common stock	(201,472)	$ (626)			(200,846)
Repurchase of common stock (in shares)		(5,005)
Cash dividends	(16,648)				(16,648)
Net income	119,981				119,981
Other comprehensive loss	7,029			7,028
Reclassification of tax effects resulting from the Tax Reform Act				118
Balance at Sep. 30, 2018	1,667,760	$ 22,911	1,664,568	3,524	(23,243)
Balance, Shares at Sep. 30, 2018		183,289
Cumulative effect of changes in accounting principle related to revenue recognition	12,679				12,679
Balance at Dec. 31, 2018	1,522,354	$ 21,940	1,671,645	(13,040)	(158,191)
Balance, Shares at Dec. 31, 2018		175,522
Net issuance of common stock under stock-based plans	14,731	$ 220	14,511
Net issuance of common stock under stock-based plans (in shares)		1,762
Stock-based compensation expense	26,029		26,029
Repurchase of common stock	(365,386)	$ (1,099)			(364,287)
Repurchase of common stock (in shares)		(8,794)
Cash dividends	(46,307)				(46,307)
Net income	342,395				342,395
Other comprehensive loss	(11,181)			(11,181)
Reclassification of tax effects resulting from the Tax Reform Act				553
Balance at Sep. 29, 2019	1,482,635	$ 21,061	1,712,185	(24,221)	(226,390)
Balance, Shares at Sep. 29, 2019		168,490
Balance at Jun. 30, 2019	1,479,412	$ 21,305	1,688,211	(7,591)	(222,513)
Balance, Shares at Jun. 30, 2019		170,436
Net issuance of common stock under stock-based plans	14,087	$ 46	14,041
Net issuance of common stock under stock-based plans (in shares)		377
Stock-based compensation expense	9,933		9,933
Repurchase of common stock	(124,763)	$ (290)			(124,473)
Repurchase of common stock (in shares)		(2,323)
Cash dividends	(15,264)				(15,264)
Net income	135,860				135,860
Other comprehensive loss	(16,630)			(16,630)
Reclassification of tax effects resulting from the Tax Reform Act				382
Balance at Sep. 29, 2019	$ 1,482,635	$ 21,061	$ 1,712,185	$ (24,221)	$ (226,390)
Balance, Shares at Sep. 29, 2019		168,490