Stock-Based Compensation - Stock Option Activity (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Number of Options
Outstanding at beginning of year (in shares)	932,500	1,116,750	1,039,750
Granted (in shares)	0	0	176,000
Expired or forfeited (in shares)	(185,000)	(184,250)	(99,000)
Outstanding at end of year (in shares)	747,500	932,500	1,116,750
Exercisable at end of year (in shares)	747,500	932,500	1,116,750
Weighted- Average Exercise Price
Outstanding at beginning of year (in dollars per share)	$ 4.68	$ 6.34	$ 8.39
Granted (in dollars per share)	0.00	0.00	0.96
Expired or forfeited (in dollars per share)	10.14	14.72	18.32
Outstanding at end of year (in dollars per share)	3.33	4.68	6.34
Exercisable at end of year (in dollars per share)	3.33	4.68	6.34
Weighted-average fair value of options granted during the year (in dollars per share)	$ 0.00	$ 0.00	$ 0.68
Weighted-Average Remaining Contractual Life	4 years 7 months 55 days	4 years 7 months 32 days	4 years 9 months 20 days
Aggregate Intrinsic Value	$ 0	$ 40	$ 27

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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