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

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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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 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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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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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.

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Equity-Based Compensation Options Outstanding (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
2010 Plan [Member]
Share-based Compensation Details
Number of options outstanding (in shares)	631,846	660,471	461,346	265,500
Weighted-average price	$ 15.89	$ 15.93	$ 13.59	$ 12.89
Weighted average remaining contractual life	9 years 6 months
Aggregate intrinsic value	$ 0
Equity Plan [Member]
Share-based Compensation Details
Number of options outstanding (in shares)	1,868,597	2,472,147	2,584,547	3,175,075
Weighted-average price	$ 4.82	$ 4.67	$ 4.68	$ 4.49
Weighted average remaining contractual life	3 years 11 months
Aggregate intrinsic value	8,809,260
Range of Exercise Prices, $12.16 – $13.75 [Member] \| 2010 Plan [Member]
Share-based Compensation Details
Number of options outstanding (in shares)	314,250
Weighted-average price	$ 13.10
Weighted average remaining contractual life	9 years 4 months
Aggregate intrinsic value	0
Exercise price range, lower limit	$ 12.16
Exercise price range, upper limit	$ 13.75
Range of Exercise Prices, $15.04 – $16.93 [Member] \| 2010 Plan [Member]
Share-based Compensation Details
Number of options outstanding (in shares)	148,096
Weighted-average price	$ 15.84
Weighted average remaining contractual life	8 years 2 months
Aggregate intrinsic value	0
Exercise price range, lower limit	$ 15.04
Exercise price range, upper limit	$ 16.93
Range of Exercise Prices, $20.68 - $21.41 [Member] \| 2010 Plan [Member]
Share-based Compensation Details
Number of options outstanding (in shares)	169,500
Weighted-average price	$ 21.11
Weighted average remaining contractual life	11 years 1 month
Aggregate intrinsic value	0
Exercise price range, lower limit	$ 20.68
Exercise price range, upper limit	$ 21.41
Range of Exercise Prices, $2.35 – $3.26 [Member] \| Equity Plan [Member]
Share-based Compensation Details
Number of options outstanding (in shares)	292,500
Weighted-average price	$ 3.20
Weighted average remaining contractual life	4 years 0 months
Aggregate intrinsic value	1,852,825
Exercise price range, lower limit	$ 2.35
Exercise price range, upper limit	$ 3.26
Range of Exercise Prices, $3.48 – $4.90 [Member] \| Equity Plan [Member]
Share-based Compensation Details
Number of options outstanding (in shares)	1,007,972
Weighted-average price	$ 4.54
Weighted average remaining contractual life	3 years 0 months
Aggregate intrinsic value	5,032,901
Exercise price range, lower limit	$ 3.48
Exercise price range, upper limit	$ 4.90
Range of Exercise Prices, $5.25 – $7.18 [Member] \| Equity Plan [Member]
Share-based Compensation Details
Number of options outstanding (in shares)	568,125
Weighted-average price	$ 6.14
Weighted average remaining contractual life	5 years 3 months
Aggregate intrinsic value	$ 1,923,534
Exercise price range, lower limit	$ 5.25
Exercise price range, upper limit	$ 7.18