Stockholders' Equity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands			1 Months Ended		2 Months Ended	12 Months Ended
	Dec. 18, 2018	Dec. 27, 2016	Nov. 30, 2018	Nov. 30, 2016	Feb. 19, 2019	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017	Feb. 14, 2019	Aug. 31, 2018	Feb. 28, 2018	Feb. 28, 2017	Jun. 01, 2015
Common Stock, Dividends, Per Share, Cash Paid						$ 0.34	$ 0.28	$ 0.245
Number of Shares, beginning of year					470,424	470,424	470,424	470,424
Number of Shares, end of year						470,424	470,424	470,424
Stockholders' Equity Activity
Number of Shares at beginning of year					239,191	229,912
Number of Shares at end of year						239,191	229,912
Preferred Stock, Shares Authorized						100,000	100,000	100,000
Preferred Stock, Shares Issued						0	0	0
Subsequent Event
Stockholders' Equity Activity
Repurchases of common stock					1,277
Treasury Stock, Value, Acquired, Cost Method, excluding Commissions					$ 21,457
Stock Repurchase Program, Cost Incurred					$ 18
February 2018 Share Repurchase Program
Stockholders' Equity Activity
Stock Repurchase Program, Authorized Amount											$ 175,000
August 2018 Share Repurchase Program
Stockholders' Equity Activity
Stock Repurchase Program, Authorized Amount										$ 100,000
November 2018 Share Repurchase Program
Stockholders' Equity Activity
Stock Repurchase Program, Authorized Amount			$ 120,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount						$ 147,417
Share Repurchase Programs
Stockholders' Equity Activity
Repurchases of common stock						10,058
Treasury Stock, Value, Acquired, Cost Method, excluding Commissions						$ 172,584
Stock Repurchase Program, Repurchase Accrual						1,827
Stock Repurchase Program, Cost Incurred						$ 141
Accelerated Share Repurchase Program
Stockholders' Equity Activity
Repurchases of common stock	720	316	3,645	11,087
Stock Repurchase Program, Authorized Amount			$ 75,000	$ 150,000
Initial Shares Delivered Under ASR Agreement Percentage			85.00%	85.00%
August and November 2018 Share Repurchase Program
Stockholders' Equity Activity
Stock Repurchase Program, Authorized Amount			$ 220,000
February 2019 Share Repurchase Program | Subsequent Event
Stockholders' Equity Activity
Stock Repurchase Program, Authorized Amount									$ 225,000
February 2017 Share Repurchase Program
Stockholders' Equity Activity
Repurchases of common stock						1,385	8,607
Stock Repurchase Program, Authorized Amount												$ 150,000
Treasury Stock, Value, Acquired, Cost Method, excluding Commissions						$ 22,633	$ 127,367
Stock Repurchase Program, Repurchase Accrual							1,259
Stock Repurchase Program, Cost Incurred						$ 19	$ 123
$1.4 Billion Repurchase Program
Stockholders' Equity Activity
Repurchases of common stock								18,142
Stock Repurchase Program, Authorized Amount													$ 1,400,000
Treasury Stock, Value, Acquired, Cost Method, excluding Commissions								$ 184,986
Stock Repurchase Program, Cost Incurred								$ 272
Common Stock Held in Treasury
Stockholders' Equity Activity
Number of Shares at beginning of year					239,191	229,912	223,850	198,109
Repurchases of common stock						15,808	8,607	29,545
Common shares issued, stock options, net						(5,824)	(1,853)	(2,914)
Common shares issued, restricted stock, net						(627)	(612)	(796)
Common shares issued, Director fees						(15)	(15)	(20)
Common shares issued, Other						(63)	(65)	(74)
Number of Shares at end of year						239,191	229,912	223,850