Earnings per Share Earnings per share narrative (Details) - 2018 Convertible Senior Notes [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 01, 2013
Debt Conversion [Line Items]
Convertible Subordinated Debt		$ 86,250
Debt Instrument, Convertible, Conversion Price		$ 32.31
Debt Conversion, Converted Instrument, Amount	$ 20,309
Debt Conversion, Converted Instrument, Shares Issued	629
Repayments of Convertible Debt	$ 65,941

Including the current and noncurrent portions, the carrying value of convertible subordinated debt, as of the balance sheet date, initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. This form of debt 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, and places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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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.

+ References

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

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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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