Debt Instrument, Comparable Yield

No definition available.

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- Definition

Debt Instrument, Convertible, Conversion Price, Threshold Trigger Price

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Convertible, Measurement Period, Threshold Percentage of Product of Sale Price of Common Stock and Applicable Conversion Rate

+ References

No definition available.

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- Definition

Debt Instrument Fair Value, Per Stated Incremental Portion on Principal

+ References

No definition available.

+ Details

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- Definition

Increase Decrease In Principal Amount of Debt

+ References

No definition available.

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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- Definition

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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- Definition

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

+ References

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

+ Details

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

+ Details

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- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

The cash outflow for the settlement of obligation drawn 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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Debt - Convertible Senior Notes Due 2021 (Details)		3 Months Ended		6 Months Ended	12 Months Ended
Debt - Convertible Senior Notes Due 2021 (Details)	Sep. 15, 2015 USD ($) $ / shares	Jan. 25, 2020 USD ($) $ / shares	Oct. 24, 2015 trading_day	Jan. 27, 2018 USD ($)	Jan. 25, 2020 USD ($) $ / shares	Jan. 26, 2019 USD ($) $ / shares	Jul. 29, 2017 USD ($)
Debt Instrument [Line Items]
Amortization of debt discount				$ 9,170,000	$ 20,112,000	$ 19,103,000	$ 17,610,000
Debt Instrument Fair Value, Per Stated Incremental Portion on Principal \| $ / shares		$ 97.25			$ 97.25	$ 96.31
Debt Instrument, Convertible, Carrying Amount of Equity Component		$ 112,600,000			$ 112,600,000
Principal payments on senior credit agreement, including term loans				9,625,000	480,625,000	$ 331,250,000	685,563,000
Loss on debt extinguishment				0	$ 76,000	$ 0	0
0.75% Convertible Senior Notes Due 2021
Debt Instrument [Line Items]
Debt, interest rate (in percent)		0.75%			0.75%	0.75%
Debt instrument, face amount	$ 485,000,000.0	$ 460,000,000.0			$ 460,000,000.0	$ 485,000,000
Debt Conversion, Converted Instrument, Amount	$ 1,000
Debt instrument conversion ratio	10.3211
Debt instrument, convertible, conversion price (per share) \| $ / shares	$ 96.89
Convertible debt, trading day threshold \| trading_day			20
Convertible debt, consecutive trading day threshold \| trading_day			30
Convertible debt, percentage of stock trigger price threshold			130.00%
Debt Instrument, Convertible, Conversion Price, Threshold Trigger Price \| $ / shares	$ 125.96
Convertible debt, measurement period for percentage of product sale price of common stock and applicable conversion threshold			98.00%
Convertible debt, comparable yield						5.50%
Amortization of debt discount				$ 9,200,000	$ 20,100,000	$ 19,100,000	$ 17,600,000
Decrease in principal amont of debt		25,000,000.0
Principal payments on senior credit agreement, including term loans		24,300,000
Loss on debt extinguishment		$ 100,000