Proceeds From Issuance Of Common Stock, Including Transaction Expenses

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Gross amount of debt extinguished.

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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Number of options outstanding, including both vested and non-vested options.

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- Definition

Number of new stock issued during the period.

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Stockholder's Equity and Stock-Based Compensation Expense - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended	9 Months Ended
	Sep. 01, 2019	Feb. 21, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants issued to purchase additional shares of common stock (in warrants)		1,820,000
Net proceeds from issuance of stock		$ 47,000
Amount of debt retired			$ 28,500
Warrant exercise price (usd per warrant)		$ 33.60
Number of shares issued or committed for issuance under outstanding stock options (in shares)				700,759	700,759	804,936
Stock-based compensation expense					$ 3,736	$ 2,508
Restricted Stock and Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of restricted stock and shares reserved for restricted stock units outstanding (in shares)				926,917	926,917	128,131	1,044,125
Number of shares granted to CEO (in shares)					152,155
Stock Appreciation Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued or committed for issuance under outstanding stock options (in shares)				963,013	963,013	530,865	1,481,541
Number of shares expired (in shares)				176,528
Number of shares forfeited (in shares)				192,000
Stock-based compensation expense					$ 2,700	$ 2,800
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
New issues of equity in public offering (in shares)		1,820,000				1,820,000
Public offering price of stock (usd per share)		$ 27.50
Chief Executive Officer \| Restricted Stock and Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted to CEO (in shares)	130,000
Chief Executive Officer \| Time based condition \| Restricted Stock and Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted to CEO (in shares)	65,000
Chief Executive Officer \| Time and performance based condition \| Restricted Stock and Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted to CEO (in shares)	65,000