Debt Instrument, Comparable Yield

No definition available.

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- Definition

Debt Instrument, Convertible, Conversion Price, Threshold Trigger Price

+ References

No definition available.

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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

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

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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

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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.

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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.

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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.

+ References

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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.

+ Details

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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Debt - Convertible Senior Notes Due 2021 (Details)		3 Months Ended			6 Months Ended
Debt - Convertible Senior Notes Due 2021 (Details)	Sep. 15, 2015 USD ($) $ / shares	Jul. 28, 2018 USD ($)	Jul. 29, 2017 USD ($)	Oct. 24, 2015 trading_day	Jul. 28, 2018 USD ($)	Jul. 29, 2017 USD ($)	Jan. 27, 2018 USD ($)
Debt Instrument [Line Items]
Amortization of debt discount					$ 9,422,000	$ 8,924,000
0.75% Convertible Senior Notes Due 2021
Debt Instrument [Line Items]
Debt, interest rate (in percent)		0.75%			0.75%
Debt intrument, conversion installments amount	$ 1,000
Debt instrument,conversion ratio	10.3211
Debt instrument, face amount	$ 485,000,000.0	$ 485,000,000			$ 485,000,000		$ 485,000,000
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 conversion 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		$ 4,800,000	$ 4,500,000		9,400,000	$ 8,900,000
Convertible Debt		412,568,000			412,568,000		402,249,000
Unamortized discount		65,477,000			65,477,000		74,899,000
Debt issuance cost		6,955,000			6,955,000		7,852,000
Standby Letters of Credit
Debt Instrument [Line Items]
Line of credit		$ 0			$ 0		$ 0