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Stock-Based and Other Long-Term Incentive Compensation - Restricted Stock Activity (Details) - Restricted Stock - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020
Number  of Shares
Outstanding, beginning of period (in shares)	279,766	214,630
Granted (in shares)	123,185	199,810
Vested (in shares)	(144,850)	(134,674)
Canceled/Forfeited (in shares)	0	0
Outstanding, beginning of period (in shares)	258,101	279,766	214,630
Weighted Average Exercise Price
Outstanding, beginning of period (in dollars per share)	$ 20.15	$ 25.51
Granted (in dollars per share)	5.68	17.16
Vested (in dollars per share)	20.82	24.26
Canceled/Forfeited (in dollars per share)	0	0
Outstanding, end of period (in dollars per share)	$ 12.87	$ 20.15	$ 25.51
Weighted Average Remaining Contractual Life (years)
Weighted average remaining contractual life (years)	8 years 7 months 9 days	8 years 9 months 7 days	8 years 10 months 6 days
Aggregate Intrinsic Value
Outstanding, begging balance	$ 3,430	$ 3,529
Granted	700	3,433
Vested	946	2,807
Outstanding, ending balance	$ 3,430	$ 3,529	$ 3,529	$ 2,447

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Aggregate Intrinsic Value, Grants In Period

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The weighted average fair value at grant date for nonvested equity-based awards issued 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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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