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Computation of Earnings Per Common Share - Narratives (Details) - $ / shares | 3 Months Ended |  |
--- | --- | --- | ---
Jul. 28, 2018 | Apr. 28, 2018 | Oct. 26, 2019 | Sep. 15, 2015
Convertible Note Hedge |  |  |  |
Shares used in computing earnings per common share: |  |  |  |
Debt instrument, convertible, conversion price (per share) |  |  | $ 96.89 | $ 96.89
0.75% Convertible Senior Notes Due 2021 |  |  |  |
Shares used in computing earnings per common share: |  |  |  |
Debt, interest rate (in percent) |  |  | 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 |
Weighted Average | 0.75% Convertible Senior Notes Due 2021 |  |  |  |
Shares used in computing earnings per common share: |  |  |  |
Average share price (usd per share) | $ 99.27 | $ 110.46 |  |

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- Definition The price per share of the conversion feature embedded in the debt instrument. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031898-161870 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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