Convertible debt principal amount of the notes percentage

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- Definition

Debt Conversion, Principal Amounts For Integral Multiples

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- Definition

Debt Conversion, Sale Price Of Common Stock Percent, Minimum

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- Definition

Debt Instrument, Additional Aggregate Principal Amount

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- Definition

Debt instrument applicable conversion price percentage

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- Definition

Debt Instrument Convertible Conversion Price Benchmark1

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No definition available.

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- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or 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

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.

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No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ 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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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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- Definition

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 outflow from the repayment 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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The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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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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Debt (Narrative - Corporate Activities) (Details) - USD ($)		1 Months Ended	3 Months Ended	12 Months Ended
	Jun. 21, 2019	Aug. 31, 2016	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jul. 19, 2019
Debt Instrument [Line Items]
Payments of principal on long-term debt				$ 45,702,000	$ 576,389,000	$ 510,209,000
Loss on extinguishment of 3.25% convertible notes due 2018						1,291,000
Cash payment for conversion of 3.25% convertible notes due 2018						$ 8,523,000
Long-term Debt				$ 433,612,000
Convertible Notes [Member]
Debt Instrument [Line Items]
Loss on extinguishment of 3.25% convertible notes due 2018			$ 1,600,000
Interest Expense, Debt			1,600,000
Unamortized debt issuance costs			$ 100,000
4.00% Convertible Notes Due 2024 [Member] \| Convertible Notes [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage				4.00%
4.00% Convertible Notes Due 2024 [Member] \| Corporate Activities [Member] \| Convertible Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 105,000,000.0
Interest rate, stated percentage	4.00%			4.00%
Outstanding amount repurchased	$ 56,800,000
Debt Instrument, Maturity Date				Jul. 01, 2024
Common stock for conversion, shares				64.1540
Debt Instrument Convertible Conversion Price Benchmark1				$ 1,000
Debt conversion price				$ 15.59
Debt Conversion, Sale Price Of Common Stock Percent, Minimum				140.00%
Debt Instrument, Redemption Price, Percentage				100.00%
Long-term Debt							$ 115,000,000.0
Debt Instrument, Additional Aggregate Principal Amount							$ 10,000,000.0
3.25% Convertible Notes Due 2019 [Member] \| Convertible Notes [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage				3.25%	3.25%
3.25% Convertible Notes Due 2019 [Member] \| Corporate Activities [Member] \| Convertible Notes [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage				3.25%	3.25%
Payments of principal on long-term debt	$ 57,800,000
Debt Instrument, Maturity Date				Oct. 01, 2019
4.125% Convertible Notes Due 2022 [Member] \| Corporate Activities [Member] \| Convertible Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 170,000,000.0
Interest rate, stated percentage		4.125%		4.125%	4.125%
Debt conversion, principal amounts for integral multiples		$ 1,000
Common stock for conversion, shares		35.7143
Debt conversion price		$ 28.00
Conversion price percentage		140.00%
Principal amount of notes, percentage		100.00%