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Equity-Based Compensation (Summary of Ranges of Outstanding and Exercisable Options) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2017
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options Outstanding	41,500	159,759	117,409	247,666
Weighted Average Remaining Contractual Life (in years)	1 year 1 month 17 days
Weighted Average Exercise Price	$ 14.73	$ 15.75
Options Exercisable	41,500
$8.00 – $10.00
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 8.00
Exercise Price Range, Upper Range Limit	$ 10.00
Options Outstanding	16,500
Weighted Average Remaining Contractual Life (in years)	8 months 12 days
Weighted Average Exercise Price	$ 9.74
Options Exercisable	16,500
Weighted Average Exercise Price	$ 9.74
$10.01 – $39.00
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	10.01
Exercise Price Range, Upper Range Limit	$ 39.00
Options Outstanding	0
Weighted Average Remaining Contractual Life (in years)	0 years
Weighted Average Exercise Price	$ 0
Options Exercisable	0
Weighted Average Exercise Price	$ 0
$39.01 – $44.00
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	39.01
Exercise Price Range, Upper Range Limit	$ 44.00
Options Outstanding	25,000
Weighted Average Remaining Contractual Life (in years)	1 year 4 months 24 days
Weighted Average Exercise Price	$ 42.35
Options Exercisable	25,000
Weighted Average Exercise Price	$ 42.35

X

- Definition

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.

+ References

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)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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

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-Topic 718
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-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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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 floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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- Definition

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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