Stock-Based Compensation (Details 2) (Stock Options, USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014
$6.38 - $7.94
Stock-Based Compensation
Exercise price, low end of range (in dollars per share)	$ 6.38
Exercise price, high end of range (in dollars per share)	$ 7.94
Options Outstanding
Number of Shares	28
Weighted Average Remaining Contractual Life	4 months 17 days
Weighted Average Exercise Price (in dollars per share)	$ 6.42
Options Exercisable
Number of Shares	28
Weighted Average Exercise Price (in dollars per share)	$ 6.42
$10.73 - $12.90
Stock-Based Compensation
Exercise price, low end of range (in dollars per share)	$ 10.73
Exercise price, high end of range (in dollars per share)	$ 12.90
Options Outstanding
Number of Shares	404
Weighted Average Remaining Contractual Life	5 years 3 months 22 days
Weighted Average Exercise Price (in dollars per share)	$ 11.57
Options Exercisable
Number of Shares	340
Weighted Average Exercise Price (in dollars per share)	$ 11.64
$13.15 - $15.03
Stock-Based Compensation
Exercise price, low end of range (in dollars per share)	$ 13.15
Exercise price, high end of range (in dollars per share)	$ 16.15
Options Outstanding
Number of Shares	478
Weighted Average Remaining Contractual Life	7 years 3 months 29 days
Weighted Average Exercise Price (in dollars per share)	$ 14.51
Options Exercisable
Number of Shares	219
Weighted Average Exercise Price (in dollars per share)	$ 13.65
$6.38 - $15.03
Stock-Based Compensation
Exercise price, low end of range (in dollars per share)	$ 6.38
Exercise price, high end of range (in dollars per share)	$ 16.15
Options Outstanding
Number of Shares	910
Weighted Average Remaining Contractual Life	6 years 2 months 19 days
Weighted Average Exercise Price (in dollars per share)	$ 12.95
Options Exercisable
Number of Shares	587
Weighted Average Exercise Price (in dollars per share)	$ 12.14

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- Definition

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ 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 (c)(1)(iii)

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

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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

-Subparagraph (g)

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

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ 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 (c)(iii)

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

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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 (c)(1)(i)-(ii)

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

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ 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 (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 of outstanding stock options, 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 (e)(1)

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

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

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

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