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Equity-Based Compensation (Summary of Ranges of Outstanding and Exercisable Options) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding	159,759	247,666	277,224	458,349
Weighted Average Remaining Contractual Life (in years)	6 years 1 month 17 days
Weighted Average Exercise Price	$ 15.75	$ 16.02	$ 19.08
Options Exercisable	134,759
$8.90 – $9.32
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 8.90
Exercise Price Range, Upper Range Limit	$ 9.32
Options Outstanding	18,938
Weighted Average Remaining Contractual Life (in years)	1 year 8 months 12 days
Weighted Average Exercise Price	$ 8.90
Options Exercisable	18,938
Weighted Average Exercise Price	$ 8.90
$9.33 – $11.73
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	9.33
Exercise Price Range, Upper Range Limit	$ 11.73
Options Outstanding	70,721
Weighted Average Remaining Contractual Life (in years)	2 years 8 months 12 days
Weighted Average Exercise Price	$ 9.74
Options Exercisable	70,721
Weighted Average Exercise Price	$ 9.74
$11.74 – $19.58
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	11.74
Exercise Price Range, Upper Range Limit	$ 19.58
Options Outstanding	20,100
Weighted Average Remaining Contractual Life (in years)	8 months 12 days
Weighted Average Exercise Price	$ 13.72
Options Exercisable	20,100
Weighted Average Exercise Price	$ 13.72
$19.59 - $32.49
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	19.59
Exercise Price Range, Upper Range Limit	$ 32.49
Options Outstanding	25,000
Weighted Average Remaining Contractual Life (in years)	7 years
Weighted Average Exercise Price	$ 25.44
Options Exercisable	25,000
Weighted Average Exercise Price	$ 25.44
$32.50 - $43.05
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	32.50
Exercise Price Range, Upper Range Limit	$ 43.05
Options Outstanding	25,000
Weighted Average Remaining Contractual Life (in years)	8 years 1 month 21 days
Weighted Average Exercise Price	$ 42.35
Options Exercisable	0
Weighted Average Exercise Price	$ 0

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=109197908&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
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-Topic 718
-SubTopic 10
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Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
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-Topic 718
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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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