It represents the rate of premium based on the last reported sales price of stock.

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Convertible debt conversion rate.

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The cap rate on a debt . A payment or receipt is triggered if the market rate exceeds the cap rate on the debt.

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Debt issuance cost amortization period.

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Amount of payment which is made for entering into privately negotiated capped call transactions.

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

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Description of the conversion terms of a debt instrument which may include the conversion ratio (including all potential conversion ratios if contingently adjustable), type of debt or equity security into which the debt is convertible, the dollars of debt or the number of shares into which the instrument is convertible (or potentially convertible into), the conversion period, any contingencies associated with the conversion terms, and the existence and amount of a beneficial conversion feature.

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

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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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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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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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No definition available.

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Long-Term Debt - Additional Information (Details)	3 Months Ended	12 Months Ended
Long-Term Debt - Additional Information (Details)	Mar. 31, 2016 USD ($) shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 25, 2016 USD ($) $ / shares
Debt Instrument [Line Items]
Aggregate principal amount of notes issued		$ 325,000,000	$ 325,000,000
Debt issuance cost amortization period	7 years
Debt Issuance Costs	$ 10,000,000
Sale of Stock, Price Per Share \| $ / shares					$ 111.20
Coupon Interest Expense		$ 12,188,000	$ 12,188,000	$ 12,188,000
Call Option [Member]
Debt Instrument [Line Items]
Debt Issuance Costs	900,000
Conversion Premium Percentage					75.00%
Sale of Stock, Price Per Share \| $ / shares					$ 111.20
Payments for Capped Call Transactions	38,500,000
Debt Cap Price					194.60
Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Terms of Conversion Feature		The Notes are not redeemable prior to maturity and are convertible into shares of the Company's common stock. As a result of the Company's one-for-twenty reverse stock split (see Note 12) and pursuant to Section 14.04(a) of the Indenture, the Notes are initially convertible into approximately 2,385,800 shares of the Company's common stock based on the initial conversion rate of 7.3411 shares of the Company's common stock per $1,000 principal amount of the Notes.
Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Terms of Conversion Feature		In addition, the holders of the Notes may require the Company to repurchase the Notes at par value plus accrued and unpaid interest following the occurrence of a Fundamental Change (as described in the Indenture). If a holder of the Notes converts upon a Make-Whole Adjustment Event (as described in the Indenture), they may be eligible to receive a make-whole premium through an increase to the conversion rate up to a maximum of 8.9928 shares per $1,000 principal amount of Notes (subject to other adjustments as described in the Indenture).
Unsecured Debt [Member]
Debt Instrument [Line Items]
Aggregate principal amount of notes issued	325,000,000
Net Proceeds Received	$ 315,000,000
Coupon Interest Rate	3.75%
Debt Instrument, Convertible, Conversion Price \| $ / shares					$ 136.20
Number of shares issued for debt converted \| shares	2,385,800
Convertible debt conversion rate	7.3411
Conversion Premium Percentage					22.50%
Unsecured Debt [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Convertible debt conversion rate	8.9928