Closing stock price on the last trading day of the year ended.

No definition available.

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- Definition

Represents the percentage of stock options that vest during the first year of employment.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of stock options that vest each month following the first year of employment until fully vested.

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

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

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

+ Details

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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

+ Details

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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

-Subparagraph (a)(1)

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

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ 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

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

+ Details

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- Definition

Period from grant date that an equity-based award expires, 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

-Subparagraph (a)(2)

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

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Period Type:	duration

- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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Stock-Based Compensation Plan (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		18 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Closing stock price (in dollars per share)	$ 20.59		$ 20.59		$ 20.59
2007 Equity Incentive Plan [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options (in years)			4 years
Percentage of stock options vesting after one year (in hundredths)			25.00%
Percentage of stock options vesting each month following first year (in hundredths)			2.083%
2007 Equity Incentive Plan [Member] \| Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options (in years)			1 year
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options exercised	$ 4.7	$ 0.1	$ 4.7	$ 0.1	$ 4.7
Aggregate intrinsic value of options outstanding	5.0		5.0		5.0
Stock-based compensation expense recorded	0.4	0.4			0.8
Remaining unamortized stock-based compensation cost	$ 3.1		$ 3.1		$ 3.1
Stock-based compensation cost recognition period			2 years 9 months 18 days
Employee Stock Option [Member] \| 2007 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options available for grant	1,921,980		1,921,980		1,921,980
Share Based Compensation Arrangement By Share Based Payment Award Contractual Term			10 years
Contractual term			10 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options (in years)			4 years
Stock-based compensation expense recorded	$ 0.1	$ 0.1	$ 0.2	$ 0.1
Remaining unamortized stock-based compensation cost	$ 1.1		$ 1.1		$ 1.1
Stock-based compensation cost recognition period			2 years 10 months 24 days