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://www.xbrl.org/2003/role/presentationRef

-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=6415400&loc=d3e5070-113901

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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.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-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=6415400&loc=d3e5070-113901

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Equity-Based Compensation (Summary of Ranges of Outstanding and Exercisable Options) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding	569,319	622,124	711,624	770,499
Weighted Average Remaining Contractual Life (in years)	4 years
Weighted Average Exercise Price	$ 11.18	$ 11.00	$ 9.70
Options Exercisable	525,569
$8.90 – $8.90
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	$ 8.90
Options Outstanding	59,175
Weighted Average Remaining Contractual Life (in years)	5 years 8 months 12 days
Weighted Average Exercise Price	$ 8.90
Options Exercisable	59,175
Weighted Average Exercise Price	$ 8.90
$9.74 – $9.74
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 9.74
Exercise Price Range, Upper Range Limit	$ 9.74
Options Outstanding	157,264
Weighted Average Remaining Contractual Life (in years)	6 years 8 months 12 days
Weighted Average Exercise Price	$ 9.74
Options Exercisable	113,514
Weighted Average Exercise Price	$ 9.74
$11.89 – $18.78
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 11.89
Exercise Price Range, Upper Range Limit	$ 18.78
Options Outstanding	148,781
Weighted Average Remaining Contractual Life (in years)	3 years 6 months 15 days
Weighted Average Exercise Price	$ 15.98
Options Exercisable	148,781
Weighted Average Exercise Price	$ 15.98
$20.52 – $23.78
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 20.52
Exercise Price Range, Upper Range Limit	$ 23.78
Options Outstanding	204,099
Weighted Average Remaining Contractual Life (in years)	2 years 4 months 6 days
Weighted Average Exercise Price	$ 22.56
Options Exercisable	204,099
Weighted Average Exercise Price	$ 22.56