Convertible note hedge fair value

No definition available.

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- Definition

Convertible note hedge shares

+ References

No definition available.

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- Definition

Debt Instrument, Collateral, Coverage Percentage

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- Definition

Debt Instrument, Covenant Limitation on Common Stock Repurchase Amount

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- Definition

Line of Credit Facility, Accordion Feature Amount

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- Definition

Note conversion obligation fair value

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No definition available.

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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

Dividend or interest rate associated with the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction. Noncash are transactions that affect recognized assets or liabilities but that do not result in cash receipts or cash payments. Part noncash refers to that portion of the transaction not resulting in cash receipts or cash payments.

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- Definition

The average effective interest rate during the reporting period.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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Amount, after accumulated amortization, of debt discount.

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- Definition

Amount, after accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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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.

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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Debt Obligations (Narrative) (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2017	Dec. 31, 2018	Nov. 09, 2018	May 10, 2018	Sep. 25, 2017
Debt Instrument [Line Items]
Long term obligations	$ 1,408,133		$ 1,401,252
Debt Issuance Costs, Line of Credit Arrangements, Net	9,300		9,800
Convertible Debt	$ 206,970		204,846
Senior Notes 2nd Term Loan [Member]
Debt Instrument [Line Items]
Long term obligations				$ 675,000
Variable interest rate	0.00%
Unsubordinated term loan and Revolving credit facility [Member]
Debt Instrument [Line Items]
Collateral coverage percentage	102.00%
Maximum amount of common stock authorized for repurchase	$ 100,000
Unsubordinated term loan [Member]
Debt Instrument [Line Items]
Long term obligations	$ 714,027		721,406
Variable interest rate	4.75%
Revolving credit facility [Member]
Debt Instrument [Line Items]
Long term obligations	$ 475,000		475,000
Accordion feature amount				$ 400,000
Line of Credit Facility, Maximum Borrowing Capacity	$ 545,000
Variable interest rate	4.74%
Credit facility, revolving credit loan, remaining borrowing capacity	$ 57,300
Letters of credit outstanding	$ 12,700
Minimum [Member] \| Unsubordinated term loan and Revolving credit facility [Member]
Debt Instrument [Line Items]
Collateral coverage percentage	50.00%
Convertible Debt [Member]
Debt Instrument [Line Items]
Convertible Debt	$ 258,750		258,750			$ 258,750
Debt Conversion, Converted Instrument, Rate	0.00%
Debt Instrument, Interest Rate, Effective Percentage	0.00%
Proceeds from Convertible Debt		$ 252,281
Convertible note hedge shares						8,111
Warrants and Rights Outstanding	$ 38,502
Unamortized Debt Issuance Expense	(5,569)		(5,799)
Debt Instrument, Unamortized Discount	$ (46,211)		$ (48,105)
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Debt Instrument [Line Items]
Note conversion obligation fair value					$ (51,300)	$ (57,369)
Convertible note hedge fair value					$ 50,600	$ 56,097