Adoption of Accounting Principled Effect on Diluted Shares

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Average Stock Price

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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The price per share of the conversion feature embedded in the debt instrument.

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-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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Computation of Earnings Per Common Share - Narratives (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended			6 Months Ended	12 Months Ended
	Jul. 28, 2018	Apr. 28, 2018	Jan. 25, 2018	Jan. 27, 2018	Jan. 25, 2020	Jan. 26, 2019	Jul. 29, 2017	Sep. 15, 2015
Shares used in computing earnings per common share:
Adoption of accounting principled effect on diluted shares				177,575
Proceeds from borrowings on senior credit agreement, including term loans				$ 0	$ 475,000	$ 423,188	$ 707,000
Convertible Note Hedge
Shares used in computing earnings per common share:
Debt instrument, convertible, conversion price (per share)					$ 96.89	$ 96.89		$ 96.89
Proceeds from borrowings on senior credit agreement, including term loans					$ 25,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (shares)								4,748,000
0.75% Convertible Senior Notes Due 2021
Shares used in computing earnings per common share:
Debt, interest rate (in percent)					0.75%	0.75%
Debt instrument, convertible, conversion price (per share)								$ 96.89
Class of warrant or right, exercise price of warrants or rights (per warrant)					$ 130.43
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (shares)					4,748,000	5,006,000
Warrant Transaction
Shares used in computing earnings per common share:
Class of warrant or right, exercise price of warrants or rights (per warrant)								$ 130.43
Proceeds from borrowings on senior credit agreement, including term loans					$ 25,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (shares)						5,006,000.000		4,748,000
Weighted Average \| 0.75% Convertible Senior Notes Due 2021
Shares used in computing earnings per common share:
Average Stock Price (usd per share)	$ 99.27	$ 110.46	$ 106.11