Stock Compensation - Fair Value Assumptions (Details) - $ / shares	1 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)		$ 1.72	$ 3.54
Risk-free interest rate		2.27%	2.56%
Expected life (years)		6 years	6 years
Estimated volatility factor		52.33%	47.52%
Expected dividends		0.00%	0.00%
Stock appreciation rights (SAR)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of awards (in dollars per share)	$ 0.17	$ 1.86	$ 0.29
Risk-free interest rate			2.47%
Expected life (years)			3 years 4 months 2 days
Estimated volatility factor			48.22%
Expected dividends			0.00%
Stock appreciation rights (SAR) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.61%	1.74%
Expected life (years)	2 years 10 months 2 days	5 years 9 months 29 days
Estimated volatility factor	52.33%	47.52%
Stock appreciation rights (SAR) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.71%	2.98%
Expected life (years)	5 years 2 months 19 days	6 years 6 months
Estimated volatility factor	54.50%	48.00%
Director shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate		1.96%
Expected life (years)		6 years 5 months 19 days
Estimated volatility factor		31.16%
Expected dividends		0.00%

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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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

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- Definition

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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No definition available.

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- Definition

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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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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 (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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