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Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
	May. 27, 2015	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jul. 17, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 40,187		$ 40,187
Total intrinsic value of options exercised				45,141
Aggregate intrinsic value of options exercisable		$ 240,069		$ 240,069
Market value of Company's common stock		$ 49.03		$ 49.03
Weighted average exercise price per share		$ 20.35		$ 20.35
Total options that were outstanding		18,378		18,378
Total options that were exercisable		8,371		8,371
Dividends declared per common share	$ 0.24	$ 0.24	$ 0.22	$ 0.24	$ 0.22
Cash dividends declared on the Company's common stock				$ 39,852	$ 36,942
Common Stock Buyback [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchased and retired				2,782
Company purchased, cost				$ 126,335
2014 Plan [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate				50.00%
2014 Plan [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate				50.00%
Subsequent Event [Member] \| Common Stock Buyback [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining stock repurchase authorization amount						$ 176,378